I'm glad the discussion helped you but "random Google articles" will actually help you more in the long run. Learning bike repair by asking individual questions is a bit like learning to construct sentences by looking up individual words in a dictionary. You need to get the overall picture of how things interact with each other, and your approach has apparently not succeeded in that aspect, or you would not still have some of the misunderstanding about chains and drive trains, in spite of owning and working on many bikes.

Further, the articles aren't random if you pick the sources I mentioned above, and then follow links to other related pages. That way each time you look up one thing you learn about several others. That's also why I recommend text tutorials as a primary source over videos, which leave out too much.