I was like that when I was young. Now all my plans involve me forcing myself to do 1 or 2 productive things a day besides the stuff I have to do, and then just calling it a day and pushing aside the rest of the stuff I probably should do till tomorrow. Or more realistically, the next weekend or holiday.
I don't lie to myself anymore, I just admit that if it's not 100% vital, it won't get done quick, if at all.
Mid 20s here, this is what I've ended up at too. I prioritize how much each thing needs to be done and then force myself through 1-2, sometimes even 3 as early in the morning as I can. Otherwise it doesn’t get done
I've found the closest thing to a panacea for this is a mixture of willingness to fail and self forgiveness for falling off the horse. Everyday is a new opportunity to get back on it. And if you're not feeling it today, it's generally ok to just wait until tomorrow (this works for me because I have to be very gentle to myself sometimes, idk if this part will work for everyone. You kind of have to [or at least, I have to] address all the other potential issues, like anxiety or depression, before the motivation to do stuff follows).
Idk why I'm posting this on a shitpost, but if it helps even one person, seems like it's worth posting.
Then you need to try habit stacking. Add 1 thing to your routine a month. 28 days to form a habit, so don't bite off an entire new lifestyle, CREATE the lifestyle over a year.
Worked for me! Got me from alcoholic party dude with nothing going on to college graduate who has a relatively decent/stable income and now I can actually plan fun things to do instead of just look for the night's drinking buddy. You never stop growing/learning so just keep at it!