This varies from person to person. Thin people can't exercise alone, but they have to eat together to have an effect. If thin people want to be fat, they should practice three points and eat seven points. If you eat well, you will have an initial effect in a month or two, but it is generally not obvious. They should keep eating and practicing. If we stick to it, it will have obvious effects in about half a year.

So the most important thing is four words: eat! Practice! Hold on!