As one of them 90's kids, the earliest I can remember is a simple DOS based racing game.
A little bit later, mostly settled on RTS as a genre, having spent time with the more classic RTSs (like Dune 2 or Red Alert 2), but ended up spending years with a more obscure game known as Outpost 2. To the point where I had a whole high-school project centered around making a map mod for it where I implemented the board game of monopoly using the in-game chat to hook into to supplement the player input that would need to go into the code in an easy enough format. All with the help of the small community that kept that title alive through the 2000s.
Never was a genre purist, as some other titles of the time caught my attention, like the Descent games, Hellbender, can't deny having played Doom 2 and some other of those early titles where so many more things could fly in terms of games as they do today. BG1 and 2 were also in there somewhere.
So, factually, I can't actually name a title that made me a gamer. It was more the exposure to games as a whole. In fact, to even list my whole repertoire of games played to date would be largely impossible, as I'd have to count the titles from before I had access to legally purchasing games. A short teaser would include stuff like The Incredible Machine (3, maybe), Empire Earth, Fire Emblem titles (5 through 7, really), even the Sims 2 and 3, diablo 1 and 2, emperor: battle for dune, C&C games down to Generals, the aforementioned titles in this post and on and on. Admittedly, my young adult life was vastly spent with an inordinate amount of play time in Path of Exile, but by this point in time, I have a steam history can rely on for a recap. Prior to that is purely memory-based and we all know how reliable that can be.
I'm not sure how much of a stretch it would be to say that if my Steam library consists of some 200 games from about 2010 onwards, there could easily be another 1-2 hundred titles that I've spent *some* time with at some point prior.
To be fair, I do have clinical ADHD and each game can only hold my attention for *so* long, depending on how much of said game there is to learn and toy around with. I will also not hide from the fact that I had ample time to spend on playing games during a decade-long depression cycle where vegetable wasting daylight playing vidja games would not be a stretch to describe my functionality back then.
