How long is it appropriate to practice in the gym every time?

It's definitely not good to go to the gym every day. It's best to go three to five times a week. People's bodies need to recover from fatigue, and then recover from fatigue, so that their physique can be improved. Exercise for about 2 hours at a time, and you can do less at the beginning, depending on your physical condition. If you have anything to ask, just keep asking!