Sounds like you aren't the most academic person in the world. That's fine, as many people aren't and never go to college and do just fine. However you can't dismiss the benefits of a degree. You should take classes at a junior (community) college and get a basic degree. It'll help when one day you realize you want a better job than flipping burgers for min wage.

Cycling is a hobby for you. You aren't going to be a pro racer, and you know that. Hobbies require money; cycling is the most cash-intensive sport I've ever seen and can possibly imagine. So you need a job.

One day you'll realize what you want to do with your life and will pursue that. Until then, stay in school and get some sort of a degree. It'll help in the future. You'll always enjoy cycling and you'll get better as a rider the more you ride, but ultimately it is just a fun thing to do.