Probably one or two SIPS.
If you don't drink with your family, your body isn't used to it, and you will get sick. You'll also get drunk really fast.
Ask your family to let you have a sip of something when you are home. Bad things happen when you don't have control and aren't in a protected place. Getting drunk with a boy is a very bad idea, and so is running around drunk- you forget not to go into the street, or other places that you would not even think were dangerous. TWO girls near me wandered out into swamps, tripped in the mud and drowned a couple years apart. They were a little older than you.
Don't drink this whole thing. And be aware that you can actually die of alcoghol poisoning if you drink too much. The problem with drinking for fun is that once you start, you don't realize what you're really doing, and you can drink enough to go into a coma. For real.