Dance: You need a child's skill: you have to start training from a very young age (usually 5 or 6 years old). By the time I graduated from junior high school, I had at least completed all the training for the amateur examination level (13). Poor basic skills, you can't get into art school (you graduated from junior high school, you can't get into art school, you can only get into art school).

Music: I don't know if you are talking about vocal music or instrumental music. Vocal music, it's not too late to start now (as long as you have a good voice, the music feels good). If it is instrumental music and folk music is not too late, western music can only choose wind music (piano and violin are too late = = that also needs childlike innocence)

Whether it is dance or music, you need to be a teacher before the exam and be familiar with the enrollment process (preferably an art school teacher and a major you want to apply for). She/he will guide you to do some "exam-oriented" training to pave the way for your admission.

Regular art colleges are not expensive after admission (informal colleges must not go, let alone high tuition fees, and there is no guarantee that you will learn anything), but the training before admission is very expensive. ........

Where there is a will, there is a way. If you really like it and the conditions are good, then work hard. Look at the Avenue of Stars. There are so many untrained uncles and aunts. Besides, you are only a teenager. If you choose the right direction, you can learn everything in time.

Good luck.