Horse racing advice? A few questions?

I am leasing a horse from my trainer. I really want to be a jockey and graduate the North American Racing Academy. I am 13 years old. My horse is a thoroughbred. He is a little slow. I want to learn to race on him without my trainer knowing. Can I use a dressage saddle to learn on at the canter? I'm saving for a racing saddle. Do you know where I could get one? I really, really, really want this. Any tips? Links? Video responses? Thank you.