Congrats on your choice and welcome!
Do your parents know and support you with your decision and have you talked to them about buying appropriate foods and what you will no longer be eating? I suggest talking to the cook about special meals and whatnot.
I want to start by saying there are really 2 ways of being vegetarian. There is the cold turkey way where you cut it out RIGHT NOW, altogether, or you take it slowly and cut things out slowly while transitioning to things you aren't otherwise used to.
Example would be:
First week: Cut out chicken and bring in faux chicken or tofu
Second Week: Cut out beef and bring in eggplant steaks (cooked in some butter with spices......but veg!) and/or tofu or something else.
and so on......
Do it at your pace, however you feel comfortable, just as long as it is done 
We have an EXCELLENT recipe section on this forum filled with mouth watering goodness, I suggest you check it out.
As for cravings, I had to fight them and still continue to do so. Every once in a while I think......you know....I could go for a burger.......but always remember, most places have veggie burgers (some are off menu and you have to ask) so there is never an excuse. Plus, by fighting cravings, I can still gladly consider and call myself a vegetarian. It makes me feel awesome. By eating meat, I know it will make me feel horrible, so why do it?
Just picture an animal screaming bloody murder and YOU could save it by saying NO to meat. 
Good luck!
EDIT:
You can by any vegetarian thing at most local grocery stores.
"For as long as men massacre animals, they will kill each other. Indeed, he who sows the seed of murder and pain cannot reap joy and love." - Pythagoras