Last week I shot the H2O Fowl Farms Adam Ginette Memorial IDPA match with my Glock 19 from t-shirt concealment.
I shot the match the way I actually carry. Glock 19 (that’s basically factory stock other than sights and a grip plug) a Crossbreed Supertuck IWB holster, and a cheap mag pouch that I’ve had forever.
Discounting the IDPA rules violations I had a great match. I shot fast, got my hits, and even had a stage win on stage 5 (of course, the one I didn’t video).
All of this to say, don’t go buy a bunch of gear before you try competitive shooting. Take what to already have, or borrow some gear and go shoot. It’s not the gear that will be holding you back.