Okay.
*takes deep breath*
Since you have proven yourself to be too lazy to read the Recruiting FAQ, I will spell out the basic information just for you.
This so-called "summer program," as you call it, is army basic training, to be more precise, two courses: BMQ (Basic Military Qualification) and SQ (Soldier Qualification). To participate in it, you have to, guess what, join the military. You go through a (occasionally prolonged) application process, and if you're lucky enough get through it without any major difficulties, you become a member of the Canadian Forces.
To do this, you need your grade 10, you need to be 16, as well as you need to be a Canadian Citizen, but you could have found this out simply by reading the Recruiting FAQ.
Since you speak of a 'summer program,' I am assuming you mean to join the Reserves. Now, the Reserves are a part-time deal, but they are still part of the Canadian Forces. You usually work one evening a week and a weekend or two a month with your unit, in addition to summer training. Since kincanucks graciously provided you with a number to call to find out more information, more specifically, which reserve units are in your area, I suggest you do so.
Have a nice day.