Is it useful to go to the gym to lose weight or to go to Sister Xiaoxing to lose weight? Have you ever tried a friend?

Where to lose weight is useful depends on your perseverance. You can lose weight by running and jumping freely at home. If you go to the gym, you can certainly lose weight. Then, as you said, be careful of your sister. She may also be an effective place to lose weight. You can try and see what you decide.