One of the first things you should do is find a club. Clubs are a good way to make friends in Amateur Radio and getting out there. There are two clubs you should join. The first one is your local ham radio club, which you can find here or here, which ever has the info you need. The second club you should join is the ARRL. ARRL hosts multiple large contests, such as Field Day. They also advocate for Amateur Radio to make sure the Amateur Radio bands don't get taken away.
YOTA (Youth on the Air) is a program by and for young amateur radio operators. They host several events, such as a summer camp where kids ages from fifteen to twenty-five can experience a multitude of things, such as contesting, antenna building, satellite operations, kit building, and much more. In addition to those activities, they hold their own contests, where they operate on HF bands using CW and SSB.