Only the best of the best... fractions of a % ever make any money racing.
You need to eat, sleep, and breathe racing... get as much exposure to everything you can get. Learn, talk to people, ask questions, read, volunteer, work in a shop, and study mechanics, ...
Many in motorsports have some kind of engineering degree. You'll need lots of math and science.
That sounds like fun. In my community, there is a small dirt track course that has races every Friday night. Cars are entered by individuals who retrofit older cars with roll bars, faster engines and stuff, all hoping for small prizes. Drivers start areers there. Even the big names do that. So, my suggestion is to see what motorsports are happening locally to you. Often, there are people who have fun building race cars for a hobby, but who are not drivers. Attend the events, talk to the drivers and owners. It may take a bit of luck, but what you're seeking is that first opportunity to race. Worst case, you may need to invest in fixing up a car of your own, but that would guarantee that you would be the driver. I have attended many of these local races and it is a great place to start. I wish you well.
The beginner motorsport training in flat surface understand the vehicle and friction of surface. Turn right or left in high speed or low speed how to handle the vehicle.
One personal advice be safe use the safety precautions.