Good career. Very tough and competitive. You have to take orders well, over and over and over, for hours. Those videos are shot hundreds of times until they are right. When you try out or are hired, if you can't follow the routine quickly you are fired on the spot. Many of the routines are taught by sequences that you must memorize.
Ballet, gymnastics, any exercise that keeps you strong and limber (and thin).
There are classes in backup type dancing popping up all over the country.
Ask your ballet teacher to direct you to one later.