Pretty cool to have a 14 year old asking these questions on his own behalf. I would imagine that you'll get some very good information from people here. I will add: pitching becomes a 7 day a week proposition, it has to be approached as a job. There is something within your program to do every day and when you have an "off" day it is to be OFF. Rest and recovery are as important, if not more important than chasing velocity. Learn how to locate, learn to command the changeup. Devote time to working on your moves to bases, have as many in your pocket as possible. At the right time, the right guy will appreciate that ability. Be the best at fielding your position and throwing to bases. Learn how to control your emotions, good and bad. Have the best body language while being a great teammate.
I know this response didn't answer your question, but with all of these characteristics you will so much more attractive when it's time to concentrate on pitching in college. Velocity will matter to a significant degree, especially if your a RHP, but a polished pitcher stands out and you have absolute control over the type of pitcher you want to become. You're velocity will be whatever it is. Good luck kid and throw strikes, unless you're trying to get them to chase.