The single best advice you've gotten so far here is to have a backup plan. The second best advice is to make sure you also understand the reality.
You use Bill Gates as an example of someone who took the risk and went all in. He didn't. He was already well versed in software and microcomputing before he took a leave of college to give his BASIC software business a shot, and backed by money from his father, he wasn't really risking anything. If Microsoft didn't succeed, he could still continue in the software business easily, and he could have easily returned to college to finish his degree. He had a very strong solid backup plan, even though the consequence of Microsoft's failure was minimal.
In your case, if you go all in on trying to become a Tour pro, you have significant consequences if you fail. If you're lucky perhaps you can stay in the golf industry, helping people try on shoes in a golf store. But you won't have any real transferable skills to other businesses or industries, and the skills you have in the golf industry will be sufficiently narrow to greatly limit your future career options. You'll be a decent amateur player without a degree, competing for jobs with other good players who have degrees. Welcome to a lifelong career in minimum wage.
Regarding the reality, I'm not going to comment on your swing or your ability to play well with your local golf pro. But what's your amateur tournament pedigree? Are you #1 on your school's golf team? Have you been playing AJGA events and winning? Placing high in state championships? As a high school senior, you're at an age where there are seemingly endless outstanding players out there your age and younger who have been competing nationally for years. They can already smoke a tough course in the low to mid 60s when playing recreation golf. But as Ben Hogan said, there is golf and there is tournament golf, and the two are barely similar. If you don't already have such a tournament pedigree, they you have to take a look at the many thousands of kids your age who are already years ahead of you down this path and recognize they are going to be competing for those same 125 spots on the PGA Tour that you covet.
And if college isn't in your plan, again take a look at the many thousands of players across the country who are competing at collegiate golf day in and day out. These were the outstanding players in high school, who already had extensive tournament experience, and now they are playing on a bigger stage. If those great players your age and younger are your competition, now look at the collegiate players as being the best of the best. With the demise of Q School, it is getting harder for someone to walk into professional Tour golf without having the college experience. How do you stack up against Beau Hossler, or Jordan Spieth? And all those players are also getting something you aren't - an education. They'll have a backup plan that will let them earn more than minimum wage. You're working in the golf store shoe department, and they're managing that store, or working in the marketing department for Taylormade, or as an investment banker.
I do a lot quite a bit of mentoring work with kids for careers in engineering and science, and I never want to tell someone they can't achieve something. It is very important that kids dream high and strive to reach things that many feel can't be attained, and it's good you have that goal. Dreaming big with an understanding of what it requires translates into lofty yet achievable goals. But there is a word for dreams without a sense of reality; they're called delusions.
