I don't think you can skip the sphere grid tutorial though?Didn't know about the OP's one, and I've played KH1 twice... dang
The big one for me was playing FFX for the first time and somehow not knowing about the sphere grid. I got up to this one sin spawn boss fight (roughly 20 hours in? I was youngish so it took a while) without ever levelling up, and dropped the game because it was too hard. I picked it back up later and realized my mistake and just demolished that thing.
I guess I just skipped the tutorial idk