I'm 15 and looking for help on my future military career. (US Marines)?

Ok I asked a question earlier and thanks for those that answer , but I have devoted myself to go to the marines. My reasons are they are the smallest branch so faster promotions? Right? And they discipline their soldiers more which I want to make me become a better man in my life. Ok back to this question, im just wanting to know if at age 15 (9th grade) what schools, camps, or any kind of activates to get into just to get ready. Yes I can ask a recruiter these questions ,and I will, but I would like to know from the people themselves. YOU!! Well for those that answer my question, Thanks, for those that have their own opinions about defending my country, keep it to yourself, again Thanks 47 minutes ago -4 days left to answer. Additional Details Ok yes I know about ROTC, im planning on doing all four years but I mainly mean like summer stuff I could do. And yes I haven't thought about shadowing someone but I sure wills ask when I see the recruiter. Thanks. 27 minutes ago Ok well what are the RAFs And tell me how u got into it, cost, locations, and time u could be there. thanks