what budget 3d printer would you suggest for a beginner?

Whatever you go with, keep in mind that for the most part the difference between a cheap ffm 3d printer and a mid-tier 3d printer isn't print quality, it's reliability. If you are happy spending as much time getting the printer to actually consistently print properly as you do actually printing stuff, then go ahead.
Cheap 3d printers are a hobby, expensive 3d printers are a tool
- My third printer, I paid $70 for, used (ender 3 pro return). It was missing several small components, one big part (top aluminum extrusion) that required some machining with a drill press, and had a bad thermistor.
  I don't think you can get a beginning printer for $100 unfortunately. Sovol and Anycubic make printers among the cheapest that are more beginner friendly (I think) than Ender, for roughly the same price. I have a friend with a Creality and an Anycubic Vyper, and the Vyper seems to be more beginner-friendly. I have two Crealitys and I love them, but both required a ton of modifications to become reliable.
  Can you check your area for a local maker space? My local library has 3D printers for anyone under 18. Universities typically have a few of different technologies (SLS, SLA, FDM)
  
  Just to add an extra data point I was able to get my ender 3 pro for $100 when it was on sale at microcenter. My experience is it works great for awhile and then I have to spend time watching videos and reading comments on how to fix random issues my ender 3 pro has. It has not been the most user friendly but hey, it was a cheap printer. I also have upgraded mine with new silicone spacers or whatever to keep the bed more level in between prints as well as a new hot end, oh yeah also the filament tube. I still love it though!

The Ender 3 v3 SE is going to be y our best bet. I run a 3D printer repair shop, and unless you are already experienced and good with assembling kit machines and highly technical of a person - you will have a terrible time with an Ender 3, 3 Pro, or 3 v2.
The Ender 3 v3 SE can be had for $200-ish at various places, comes with auto leveling which even handles all the Z-probe offset stuff, so there's no need to get yourself confused with terminology, it already has a direct drive, and PEI build surface, all the things you'll end up spending another $200 on to put on an Ender 3 of a previous generation.
Don't start your 3D printing journey for $100 unless you have a highly technical acumen or you will have a terrible time. I know the others are trying to be helpful by suggesting machines to you that fit within your budget, and it's certainly possible to start out that low -- but the better advice is just to get something slightly better. It'll make the difference between you hating 3D printing, and loving it.
- Just adding onto this as someone who got an ender 3 V2. This comment rings so true because I tried and tried to get the printer to work how I wanted for months before I just gave up. Flash forward almost 2 years and I got a much nicer but not crazy (~$400 if I recall) and it's such a night and day difference. I actually quite enjoy printing now, whereas I just kinda thought it wasn't for me with my first printer. Turns out cheap tools really do give cheap results
  
  Adding onto this as someone who bought an ender 3 pro years ago and got it printing beautifully within about 6 months.
  Yes, you have to have some knowledge and skills, but it is quite possible to get those printers working nicely and reliably. Of course, between the cost of upgrades and the time spent it's only worth it if you want to learn or practice.
- I had a 3 V2 and sold it. Spent so much time and money and still hated it. Will I like that one better?
  
  Yes, even the v2 required a lot of assembly and you have to deal with eccentric nuts and delrin V wheels and crap in order to make it print right. The v3 has proper linear rods on the Y axis, no wheels to adjust the bed, everything assembled with like 6 screws. It's leagues ahead of the v2.
  
  Look at Sovol or Anycubic in that price range. I don't have direct experience with either. A good friend of mine had two Anycubics at one point last year and he said they were easier than his Creality.

im looking into making mini figures and painting them
Boom, right there should limit your section to SLA/resin printers, not FDM as most people here are suggesting. At $100 budget you're down in the absolute basement of printers, and will have to find a machine on sale. Good news for you is that this is the month of sales (Black Friday month). You are looking at either an Anycubic Mono (out of production, I think) or Mono 2 when they go on sale, or mayby an Elegoo Mars - I'd expect to see it between $99-119 sometime this month. (there's a monoprice mini SLA printer for $70 out there, but I don't know how good it is)
There are two things to know about resin: the liquid used is toxic, so someplace with ventilation and a supply of cheap latex/vinyl/nitrile gloves are a must, as is a workspace which can be easily cleaned (they sell silicone mats...its a good idea; you might try ordering misc stuff from TEMU for your accessory list to save some cash) and a roll of paper towels is going to be necessary. The second is that standard resin requires 95% or higher isopropyl alcohol (IPA) to clean the prints, and to clean up the machine parts. That can get expensive, too - so SKIP IT and get Water Washable resin. It will cost more, but the ease (and lower odor) in clean up will be worth it, especially if your parents would rather you not be slinging flammable IPA around the house.
You do NOT need a dedicated wash and curing station. It's a luxury you can't afford, so just skip it (for now). There are lots of videos about how to clean parts using a two-bin or three-bin method and they just use cheap dollar-store plastic bins or used buckets (do not use tupperware you eat from...water washable is still toxic, okay?). Then, just set your prints in the sun for a few minutes - it even works on a cloudy day (clouds only block a fraction of UV).
You should be able to make table-top sized miniatures for painting in one go, or make them as two or three parts for bigger models. The detail you get out of an SLA printer will be worlds better than an FDM (extrusion) printer and require a lot less sanding, filling, and misc post-processing prior to painting.
Quick edit: @QuietStorm@lemm.ee - Creality is also having a sale this month and there are two SLA printers on sale in the $99 range. The nicer (bigger) one is currently out of stock, but you might check back and see if it comes back in. Nearly all of the small SLA printers in this range are very similar, though you should read up in their forums just to see if there are some crazy problems everyone is having with a specific model (no news is probably good news).
- Great advice. I would add one thing, people upgrade their printers all the time and sell the budget ones they started with on eBay/FB Marketplace, etc.
- I wouldn't recommend water washable even though it's cheaper not using IPA it's more cumbersome and possibly expensive to dispose of it. You can just dump it down the drain
  
  Normally, I would agree. For a teen living at home and (based on the price range) without a dedicated space, I think it's the preferable of the two options. Having known someone severely burned by an errant spark around IPA, and with the added complications of disposing of contaminated IPA, waterborne is the lesser of evils. I 100% agree that I should have pointed out that "water washable" doesn't mean rinse/clean off in a sink that leads to a private septic or public treatment system.

Absolutely one of the Ender 3s. Easy to find around $100, especially if you live near a Microcenter. They are such popular printers that any problem you may have has already been asked and solved.
If you're mainly interested in figurines, then a resin printer will give you better quality. But it comes with smelly chemicals and more work/cleanup.

Amazing summary by Angus of Maker's Muse (imo one of the best 3D printing channels): https://youtu.be/k4Cc_3G4mpc
Stock Ender 3 is a hassle that can be so frustrating you'd drop the hobby altogether. If you want to get it as a platform for tinkering and modding, then go ahead. If you want it as a tool, get something reliable. Even investing a little bit more upfront might save you more in the long run. A broken cheap printer doesn't make any money after all.
And one more note: if you want to focus on minis and want a decent quality, FDM might not be the best choice.
- Here is an alternative Piped link(s):
  https://piped.video/k4Cc_3G4mpc
  Piped is a privacy-respecting open-source alternative frontend to YouTube.
  I'm open-source; check me out at GitHub.

If you plan on printing small things, I'd recommend checking your library first. My library has one that's free to use, I just have to stay at the library while it's printing, and it has to be while that section of the library is open, which is usually 4 hours at a time.
I've seen other libraries that charge a small fee to print.
This way you can get your foot in the door to make sure you enjoy it, and by using their machine/software you can get a feel for what you might want in your own printer.

Double your budget at least or be willing to learn the ins and outs of how 3D printers work at a basic level Be sure to check out the Tomb of 3D Printed Horrors on YouTube if you are into minis
https://www.youtube.com/channel/UC5Lbnd97HV3rU98gcwHklzQ
- Here is an alternative Piped link(s):
  https://www.piped.video/channel/UC5Lbnd97HV3rU98gcwHklzQ
  Piped is a privacy-respecting open-source alternative frontend to YouTube.
  I'm open-source; check me out at GitHub.
- Enders print just fine but tend to be a bit more maintenance-heavy
  https://photos.app.goo.gl/QQwPthUBj9zVNfiCA
  
  You'll be limited to PLA and PETG for filaments
  My first PETG print

If your goal is to make mini figures, what you want is an SLA machine. They are much better at making small detailed objects than FFF. However, it will definitely cost more than a cheap FFF machine like an Ender 3.
The Ender 3 variants are cheap and a great platform if you are OK with tuning/tweaking things. If set up properly they work great and are pretty reliable. But of you want something that works out of the box and doesn't need any tweaking/tuning, you will probably be disappointed with it.
- Also resin is kinda dangrous and more tedoius. Dont get resin on your skin and the fumes are pretty bad, you also need ventualtion.
- You can get some surprising detail out of an Ender 3, especially if you pop on a smaller nozzle.
  
  Sure, you can print minis with an FFF machine. But there's a reason the mini printing folks primarily use SLA. For that particular application, it's significantly better. I say this as someone who uses an Ender 3 and is quite happy with it. If my main goal was printing minis, I would probably want an SLA machine instead.

Sovol SV06 works pretty great for me :)
- Same here. SV06 was my first printer a few months ago. I've printed for a few hundred hours without issue. Very easy to upgrade the software with a raspi and mainsailos.

100 is pretty tight, but you could probably find an original ender 3 for that much. It's good for beginners because you assemble it out of the box which gives you a feel for how to adjust and repair it, it's very modular so you can upgrade parts or add modules easily, and overall it prints pretty well right out of the box. Overall, definitely a solid choice.
One downside is no case, so ABS and other high temp or toxic filaments are no good, but PLA will print perfectly fine.
Another downside is no removable bed (they make removing the print easier), but you could easily buy one online or use tape.
If you go with the ender, make sure to get a program like Cura (free) and a micro SD card for slicing and transferring print files. You can also hook it up directly to your computer with mini USB, but that's been finicky for me. Also mini USB is old as hell and I doubt his have one laying around.

You won't get a good printer for doing minis for $100. Just the extra supplies that go with safely resin printing would blow out your budget. Even if you do find a decent $100 resin printer.

People might not agree but a prusa mini is a great reliable beginner machine but sadly way over budget. If you can find a secondhand prusa mk3 or mini within your budget I'd recommend that. They are very repairable and reliable and god for high pression prints. The best thing about a prusa is the huge amount of guides and resources online where you can find help for absolutely everything should you have problems. There's literally not a problem that has not already been described and solved on a prusa printer making it good for beginners. If you are going to make small high quality prints you should also buy a 0.25mm nozzle and you'd be amazed of how fine detail you can get (and long print time sadly, but no way around that)

Sounds like you might want to check out something from maybe Elegoo, AnyCubic, or Photon: Resin printers are unrivaled when it comes to detail/minifig printing.
Resin printers are also much easier to assemble and calibrate.
Keep in mind that you'll also need to buy or build washing and curing stations and set aside funds for the resin itself too. When working with resin, personal protective equipment and ventilation is also very important.

I personally recommend the ender 2 pro to all my friends who just want a taste of getting into it. You can get em pretty cheap online, or at microcenters. They work well pretty much out of the box, but simple enough to get you to learn tuning them. And they come with a magnet removable build plate.

Elegoo has some preowned printers. For under $100 you could get a printer a few generations older. If you're doing models, like others have said, it's probably not what you would need. If you want the practicality of printing out prototypes or cool objects then this is more of what it's for.
https://www.elegoo.com/collections/pre-owned-3d-printer/products/pre-owned-elegoo-neptune-2d-fdm-3d-printer

Ender 3, any, check ebay. Plastic is cheap on AliExpress. Mid quality though but it works.

I orginally bought an ender 3 and had had it for about a month before i returned it. Back when i bought it, in 2020 creality were swapping out parts, for cheaper alternatives some of which had defects like xt60 connectors for the psu. Which would catch on fire, i took that money and bought an i3 mega S from any cubic. It ran for about a year in a half until the 16pin cable burnt out and i decided to mod it. I switched the board for a duet wifi and the hotend for a hemeria and just recently upgraded to revo. The printer is rock solid and works well, the ender 3 is good if you want to tinker and learn about how a 3d printer works. But if you just want to make parts l, id suggest looking at other printers that are a little more expenisve, trust me you thank yourself.
It looks sketch but it works well

Monoprice Select Mini V2, I've used this little guy for a few years now, and it's rock solid
- I would say anything but this one if you're looking for a printer as a tool. My mp select mini v2 has been wonderful for me but thats because I wanted to learn electronics and have 3d printing be my hobby. Not have it as a tool.
  This printer has a mandatory bed rewiring that if not done can cause a fire or the printer to lock up. Has a odd z-axis screw that needs to be replaced as it has weird magic numbers to work with for nonstock firmware, and the board causes the motors to be incredibly loud. A bed plate that is recommended to have a glass plate added to it for adhesion and to prevent warping as it's only 1mm thick. And a very limited 120mm build volume.
  I love this thing, it taught me soldering, it taught me about electronics and voltages, how to repair and tune a printer. The fact that the motors didn't make the printer loud but stepper drivers do. How fusion 360 and sketchup work. Plus the amazing part of gcode changes like arc overhangs.
  I'm finally starting to be very happy with mine but its a ship of Theseus situation now.
  I'm currently building a voron and utilizing my printer and my coworkers stock ender3. And tbh I love the ender3. Its great, and at your budget price range it'll do most things. $100 won't be great for anything safe to use resin wise. So before you make a jump for ender3 look up the differences between fdm and resin prints as ender3 is fdm.

As someone who owns an Ender 3 v2, a Bambu p1p and an Anycubic Mono 4k, here are my thoughts... If your goal is to print and paint tabletop minis, you do not want an Ender, SV06, or even a Bambu labs printer. Even if you swap out the nozzle for a smaller one, paint and washes WILL absolutely show layer lines, unless you're willing to do hours of post processing, filling, filing and sanding. FDM is not your friend in this regard. You can, by all means, get acceptable quality prints if you're willing to spend months calibrating, tuning, failing and burning through filament with printers in your price range, especially once you start upgrading / fixing your printer (ask me how I know). If, on the other hand, tabletop minis aren't your main goal and more functional parts, or larger decorative pieces are what you're after, I cannot recommend an FDM printer enough. Cost savings on filament vs resin, speed (kind of), selection and community support are light years beyond the SLA / resin printers. I would try to avoid the cheaper Ender printers however, as other have stated and I can attest, you will be spending a lot of time calibrating and troubleshooting, and eventually throwing money at it.