In addition to exercising muscles and strength, it can also enhance cardiopulmonary function, such as improving vital capacity.
Different strokes focus on different parts. It's good to exercise your abdominal muscles just by swinging your butterfly legs.
Freestyle exercises the whole body.
Backstroke is a swimming stroke suitable for girls, which is good for listening and speaking.
This kind of exercise is not to enlarge a muscle, but to get to know each other. Muscles of the same size become stronger and the muscle proportions are more coordinated.
I don't know if you are satisfied with my answer.