My advice: get hooked in with a ballet academy, and get the teachers there to make a committment to your professional training.  Do the summer programs as well.  Avoid just doing open class, since you'll never become a professional that way.

I got my professional training in Boston, and probably could not have done so in NYC.

Finally, you need to do it somewhere where you can pay for the ballet training and your living expenses.  Where that is depends on which relatives you can live off of, and what employable skills you have outside of dance.