Tablet with no wifi? (Configurations, ADB etc)

Hi,
I was always using my old android tablet, that I thought I had removed/blocked from the router. It was working out really well, I would preload stuff onto it like documentaries etc. via my pc. That way I felt safe taking my tablet with me into my bedroom. However I have realized that I didn't actually block it from the router. And can't really, as a simple router reset can delete that block.
Now, I don't really have a way to access internet on my main profile (deleted browser via adb and locked settings). However I can access everything on a guest profile. I tried to install blockers, but on the guest's profile it shows an error when I try to install any software ("parsing" or "not enough internal memory").
I know some tablets have a physical wifi antenna underneath the cover. But since I changed the battery just a couple days ago, I know mine does not have such an antenna that could be removed.
I'm wondering how I can remove the access from guests.. maybe I can try the adb method while I'm logged into the guest profile? I don't even remember all of that, it's been so long.
I guess downloading adb tools and then trying adb devices and adb pm packages is worth it. Then something like delete 0 com.app.application. Right, tomorrow I must try