Your GPU might be having problems, but the other problems you list sound like either a bad hard drive or a virus / bad windows install.
There are several utility programs you can download that will check your hard drive for failures. I would back up any important files and then run those. If the hard drive is bad, replace it. Either way you will probably want to re-install windows from scratch.
You can do your own oil changes if you've got the time and tools. If not that, I'd find a local mechanic that you trust and get all your work done there.
Chain quick oil places usually get things right. But they don't have the tools or skills to fix things if they mess something up. They also tend to employ bottom of the barrel people who tend to not care about their work.
If you read the little summary, the test drive was in north Africa.
AntennaPod is great, free, and has no ads. Pretty sure it's open source too.
Sounds like you learned a lot. As far as the belt tensioner and not being able to budge it, usually stuff like that is a matter of leverage. You probably just need a breaker bar. Those are basically a longer version of a ratchet and are very useful for tight bolts. Usually they are pretty cheap too.
It's less convenient, but you can just not connect the TV to the Internet at all. You can connect a computer (pi or something similar) to that in order to play videos or stream from. Or an Xbox / PlayStation for ease of use (yes I know those have privacy problems as well but they are much less intrusive).
Another thing you can do is set up a pi-hole on your network and blacklist all the domains your tv uses for ads and tracking.
It might just be the image perspective, but your monitor looks way too low. It should be at eye level. Otherwise cool station, and sweet find with the desk.
It's not a glove, it's a long sleeve. Only darkeyed women would wear a glove.