Well, i don't know the answer. But i think you need to provide more info here about what you're trying to do here... Do you want an adblocker? Something to suppress trackers? Something that prevents your TV to send telemetry home to its manufacturer? Something so your ISP can't see which sites you visit?
Do you want an android app? Something you can install on your home router or raspberry pi? Just a plain DNS service for your windows network settings?
Mostly I try to secure my Android phone. I know that I cannot have a VPN and a firewall running at the same time (why Googla hasn't gotten that right yet is beyond me). Hopefully Rethink will do this at some point. No ads and tracking protection are a must. Android allows to set a private DNS natively, so an app is not a must, but if it offers an advantage I will do it (e.g. NetGuard + Private DNS or just Rethink).
You can get some of this with a pi hole/vpn setup. There’s actually a really nice one you can get as a droplet (basically a virtual machine) on Digital Ocean.
Alright. 'pi hole' is something i tried. and 'adguard home'. But this doesn't really fulfill the requirements if you want something for your android phone.
i think installing adguard-home dns, a firewall and vpn endpoint on a v-server and then connecting with your phone to the vpn would solve all issues. including firewall and dns at the same time (because then it runs on your server). but you'd invent and maintain a whole privacy service yourself.
if you don't want all of that, you're probably better off using an existing service or app.