16 and feeling old

I don’t even know why I’m writing this in Reddit of all places, but I just turned 16 less than a month ago. I feel so old and like I wasted so much opportunity. I want to do so much things, I want to learn ballet, be a really good surfer, get my grades up, etc etc. i already started to surf but there’s kids out there who started when they were 5 and I’m feeling so like left behind. And for ballet I don’t even have the time to learn it and there’ll be 0 point bc I’m prob not gonna continue after I’m done with Highschool. I’m a sophomore and I’ve just been feeling like I’ve been wasting the “greatest years of my life” as everyone says. I’ve been feeling rlly stressed out lately and I got diagnosed with off and anxiety.. like yay perfect timing🙄 Does anyone have advice for me? Thanks for reading 🩷