any schools for adult ballet beginners ?

Recreational ballet is for anyone of any age. If you wish to perform you need to find a school that has adult beginner ballet classes that also lets the adult students take part in their recitals.

The best place for someone your age who wants to start ballet and really learn properly and achieve their personal best may be at an open adult class in a ballet academy school that is the affiliate feeder school to a professional ballet company. While it is no part of their preprofessional training, there you can be assured of both proper training in a proper facility along with cheaper classes than small studios ( most often.) However those classes do not come with performance opportunities.

If you happen to live in CA there is Anaheim Ballet school. It is a recreational ballet school/company with a strong internet presence. They are known for training older dancers and will put them in their performances too if they have enough talent ( gifts) for ballet of body, facility and musicality. Ultimately how well you do will depend on your natural gifts along with the best training you can find. Not all ballet training is equal as anyone with little or poor trading can call themselves a ballet teacher. If you were thinking ballet career that would be impossible for someone your age even if you were born with all the right gifts. Training for the ballet is intense and takes full time training for many years. By the time you would be ready you would be at the age most dancers have started to retire from the ballet. For that reason you gave aged out of professional level trading.

Big cities with a strong dance presence like NYC, Philly and Chicago will have more training options available for a beginner your age. If you don't live in the USA, then just look for adult or teen/adult beginner ballet classes in your area.

It depends on your location but I am sure they have them everywhere, just look for recreational ballet classes in your area they must have some nearby, and it is more than unlikely but there is no harm in doing it just for fun <3

There's a good one in Swindon