Coming out and transitioning in high school can be scary, but you'll get through it. The biggest thing you need to do right now is find people that support you and learn to drown out the people that don't. Whether its friends, family, or anyone else you need to start building yourself up a support system full of people who love you for you. Like haeden said, going to an LGBT or GSA group at your school is a good place to start. Come out of the closet to people as you're comfortable, and don't feel obligated to come out to anyone if you aren't comfortable. Also, transition at your own pace and it doesn't have to be medically. Whether its cutting your hair, dressing more masculine, binding, or packing, these are all ways to start feeling comfortable with yourself and start transitioning that won't necessarily cost you an arm and a leg. You'll make it man, and I'm 16 as well so feel free to message me if you'd like. 🙂