Your question is very broad and probably won't be answered with any great detail.
Take the advice that's been given to you, and take some breaks from all of that schoolwork and community service you'll be doing to read posts here. I've been a member of Greekchat for about a year now, and I now know a whole lot of information about the Greek system that I never learned in the 5 years since I first became a part of it. If you just read, use the search function, and learn, I'm sure you'll be well-informed come two years from now when you start recruitment.
Good luck