Hey Christy, welcome! There are many people who are transitioning at your age here so I'm sure you'll find people to relate to.

One of the most important steps is to find a gender therapist, they will be the most helpful in your transition and being able to start hrt. There are so many things you can do to help you feel more feminine. You can try shaving, wearing more feminine clothing, changing your voice if you wish, make-up and growing your hair out! These changes can just be subtle ones too if that makes you more comfortable for the time being. Try experimenting at home too, this will give you a space where you can be yourself with the support of your room-mate.
Try looking online for some transgender support groups around your area, they can be very helpful and offer great support. Good luck and don't let anyone get in your way of being who you are. Their opinions are ignorant and have no basis to them.