So there is nothing new here. You already know that to lose fat you’ve got to be in a caloric deficit. You also know that lifting weights and working out along with eating a good amount of protein (0.8-1.2 g/lb of lean body weight or 2 g/kg of lean bodyweight) will definitely help. Same goes for building muscle. To make your muscles bigger, you’ve got to be in a caloric surplus (even a tiny one is ok), get in a lot of protein and lift weights. ~ Berceste