Whats a good way to build protein?

To eat it: You don't build protein. It is being built in your body from its components - aminoacids. To help your body build more protein, you need to consume more of the build blocks - aminoacids that are found in animal and vegetable protein. So, in other words - eat more protein rich foods - meats, dairy, eggs, less so legumes.

Eat more & exercise: Food is made up of carbodydrate (4 calories per gram), protein (also 4), and fats (9 cal/gm). Typical diet may have 15-20% of calories in proteins (15-20% fat). Suggest increasing protein to about 30-35% of diet. Drink a lot of water, seltzer with lemon etc (if 160 lbs, drink about 70 ounces -really). Then, exercise (brisk walk for 30 minutes, light weights) to convert fat to protein in muscle.