I want to make it on Broadway someday?

I want to make it big on Broadway someday (im only 13). But no one in my family supports me and its really upseting. I do musical theatre camp in the summer and during school participate in the drama club, musical theatre troupe, and chorus/chorale/boys choir. I havent tried going for local theatres yet but I am going to try when Im a bit older (younger kids seemed to be turned down more). EVERYONE IN MY FANILY WANTS ME TO BE A DOCTOR OR DENTIST BUT I DONT WANT TO !! please help me wih my family problem and some tips to make it on broadway