There are two kinds of weight loss, muscle gain and fat loss. What you're talking about now is muscle gain. Muscle is protein in plain English, and fat is fat in plain English. After knowing this, it is very clear. Can you gain muscle without eating meat? It's difficult, because your consumption is greater than your supplement, so muscle growth is difficult. But you can eat many foods rich in protein, such as egg white, protein powder, beans and grains. But from the point of view of nutrition and fitness, it is necessary to eat certain lean meat such as beef and fish. Just don't eat fat.