First of all, losing weight and gaining muscle are two different fields. Drinking water is good for reducing fat. Drinking more water at ordinary times is good for improving metabolism, and the result of improving metabolism is of course good for losing weight. However, this does not mean that you can simply lose weight by drinking water. In fact, you can lose weight quickly in a short time because of single nutrition and insufficient calories. But no matter how healthy and delicious the food is, you can't just eat one kind for a long time. Long-term use of this diet can easily lead to malnutrition and do great harm to the body. In individual methods, eating a single food is easy to accumulate substances that affect the body. For example, eating 5~6 eggs a day "boiled egg diet" can easily make your cholesterol content exceed the standard.
Protein's supplement is very important for strengthening muscles. Muscle fibers are torn during exercise, and then they are restored and enlarged by supplementing protein. That's it in a nutshell.