First off, you need to settle down. You think people are going to "hate on you" for wanting to join JTF2? Hardly. However, people will be questioning your motives when you come here and start with a post like this.
Second..."contribute more then a basic infantry man"? Really? You think that the average Infantier doesn't give all he's got when he's outside the wire? JTF2 may have different tasks than the rest of the CF, but that does NOT mean that everyone else in uniform contributes less to the protection of Canada. And don't forget that before you even set foot inside JTF2 selection door, you're going to have to be one of those you say doesn't contribute as much. JTF2 doesn't recruit off the street, and even people who've been in for years still have a tough time with it, and not just physically.
If you want to be a member of JTF2, or any part of CANSOFCOM, you're going to need more than physical fitness. A good portion of it is about attitude. One of the most impressive things about them is not their fitness, skill at kicking down doors, or anything like that. It's their ability to present themselves to the rest of us as. If you were talking to a member of JTF2, you shouldn't even know it. They don't go around bragging, nor do they act "high speed". Some of the guys I've met from that unit were the nicest guys I've seen, and I never would have known if I hadn't been told beforehand.
You're 15, so you've got plenty of time before you'll even have a chance to join, so if I were you, I'd be constantly re-evaluating my reasons for joining right up until you sign the dotted line. Again, it's more than just being fit and motivated to "take the fight to the enemy". You need the proper attitude for it. And frankly...I'm not seeing it right now.
That being said, if you're still bent on being part of Canada's best, I wish you good luck.