Great question! Protein is really important to eat because it helps build bones and muscles. It acts as a building block for enzymes, hormones, and other body chemicals that are necessary for us to function. Hair and nails are also made up of mostly protein.
As you mentioned, both chicken and cow’s milk are dietary sources of protein. Other animal sources of protein include turkey, beef, fish, and eggs. Dairy products such as cheese and Greek yogurt also contain protein. If you do not eat many animal products, vegetarian sources of protein such as beans, lentils, tofu, tempeh, seitan, nuts, and nut butters are great choices.
It is important to have protein with every meal so your body can function and grow the best it can. In general, meals and snacks should be balanced and contain all of the food groups, including protein. For example, you could have Greek yogurt with granola and fruit for breakfast, nuts for snack, a chicken sandwich for lunch, cheese with crackers for snack, and tofu stir-fried with vegetables and a brown rice for dinner. If you are not familiar with many vegetarian sources of protein, try some out to see which you like.