One more thing, fitness just needs some fat. I don't think it is easy to gain weight. I have never been able to gain weight. . . .
You can burn off body fat through training, which can strengthen your body (you can do aerobics after practicing equipment). This is not a matter of a day or two. You should carry out scientific training for a period of time, combine work and rest, and pay attention to rest and relax your muscles during exercise, otherwise you will develop dead muscles (muscles lose elasticity)! ! ! ! During exercise, you should fully supplement nutrition, eat more vegetables and fruits to lose weight, dietary fiber can clear the intestines, and vitamins should be sufficient. During exercise, you should match a certain amount of salt water (don't binge drink), and you can drink some fruit juice made by yourself after training. . . . .
You'd better find an experienced teacher to teach you, and be careful not to get hurt. Very painful. I used to practice alone, but now my injury has branded me with sequelae. Even if you have strength and explosiveness, your muscles are still asymmetrical. Now you should correct them slowly. If you are seriously injured, you can't practice explosive power. . . . . This is my experience! !