So... I recently installed Ubuntu on one of my old PCs out of curiosity, and it was working well.
My PC doesn't have an in-built wi-fi adapter so I use a USB one, and since wi-fi was slow anyways, I used an old router as an adapter and now I have a wired connection to the old router while the old router accesses the wi-fi of the main house router. Now get this: one day, I log in, and there is no wi-fi symbol, no wired connection, nothing.
I tried the solutions posted on this thread, as it matched my problem the closest: https://ubuntuforums.org/showthread.php?t=2491006
Are there any tests I should run? Or data that I should post?