This was literally all the way back in like, 1992 or whatever. I got a Sega Genesis for my birthday, I put both it and a TV in my room, and then I noticed there were a few games for it that my parents pointed out to me. Sonic 1, Sonic 2, Earthworm Jim, and I think some other ones. I started with Sonic 2, but couldn't really beat any of the other games in my collection, so I just kinda slowly collected Sonic games anyway, looked up cheats, and saw the other levels that way. Then after I grew up and matured, I tried, y'know, actually beating the games as like a 20-year-old, and now I can basically beat the entire classic trilogy in my sleep. I've yet to get a game over in Sonic Mania.
But yeah, more to the point, I started where Sonic did. On the Genesis.