Installing android on unknown device

In My Humble Opinion
1

I have a tablet that worked fine while I was in China, but is near useless here in the UK, probably because it has bloatware on it that is trying to connect to a Chinese server or whatever.

So I’d like to just “wipe” it with a new version of Android. But this is easier said than done. I’ve gone through some tutorials that involve installing Stump and TWRP but they don’t recognize the device, so they refuse to do anything.

Is there a “nuclear option”? I can risk bricking the thing, as it’s essentially a brick right now anyway.
I know the chipset, screen, memory info. I was able to root it.

2

I was going to say “About Tablet” should have some identifying information, and then you can look up tutorials re. flashing that model. TWRP has a list of officially supported devices for instance; similarly check if there is a build for it under LineageOS:
https://wiki.lineageos.org/devices/
If it’s not there, check also XDA forums