No foundation: you can go to a certified fitness instructor training institution recognized by the State Education General Administration for professional training, and then take the examination organized by the school. After passing the examination, you can get a fitness instructor qualification certificate.
It takes 2500-3200 (seven days training) to independently verify the national certificate of junior fitness instructor (not recommended, because it is difficult to pass without foundation).
If you want to learn a fitness instructor systematically and get a fitness instructor certificate, the fees of each training institution are different, and the training time and fees are different according to the courses you study. Time 1-3 months, and tuition is about 7000- 16500.