If you want to make it to the highest levels, here’s a good article on the basic training process and metrics you need The Making of a Pro Tour Rider | TrainingPeaks
If you want an entertaining general description on life as a pro rider in the US, (spoiler - it kind of sucks) read this book - https://www.amazon.com/Pro-Cycling-10-Day-Euro-ebook/dp/B00KFN7LLI/ref=sr_1_1?crid=3DCFU4JJD6E0Z&keywords=pro+cycling+on+10+a+day&qid=1638284613&sprefix=Pro+cyc%2Caps%2C180&sr=8-1
FWIW - in any sport, it is about 1000x harder to get to the top ranks than normal people realize.
That being said, don’t give up on your dream. Cycling is probably about the easiest sport to go “pro” if you simply define pro as winning money or getting some sort of “sponsorship.” Almost all local races pay cash prizes, even at the lowest levels. I completely suck as a cyclist and I did not start racing until I was almost 50. But after a 10 year “career,” I have lifetime earnings of well over $500 in cash and merchandize and I get a 10% discount on bikes through my team from our bike sponsor. I am not above claiming the title of “professional” in the right company even if it is a bit tongue in cheek 