If a juvenile is incarcerated in my state, the institution is obliged to provide schooling. I would think it would be the same in other states as well. This means that 30 days in a juvenile facility shouldn’t delay your graduation. If you have a lawyer, they may be able to give you more information; since it’s coming up so fast, you’ll at least find out during your intake. They should know the best way to transfer credit for the classwork you do there to your high school when you’re released. You might ask how that works - usually, it’s arranged through the school counselor. As for college, this experience will really make your personal essay stand out!
It’s only natural that you and your parents are very upset and thinking that you’ve ruined your life, but that’s not true. You made a very serious mistake and you’re old enough to face the consequences. That doesn’t mean your life is over or your future is doomed. This is a learning experience, a harsher one than most kids your age get, but an opportunity to grow a a person nonetheless.
Good luck!