MACRONUTRIENTS FUNCTION IN OUR BODY

Macronutrients are the nutrients that your body needs in large amounts, which include fat, carbohydrates, and protein. They're the nutrients that give you energy and are often called "macros".

Macronutrients contain the components of food that your body needs to maintain its systems and structures. You need all three macronutrients as part of a healthy diet, so you shouldn't exclude or seriously restrict any of them. 

How Much Protein Do You Need?
Protein is essential to many of your body's functions, including:
Tissue structure
Hormone system
Metabolic system
Transport system
Enzymes that regulate metabolism
Balancing the acid/base environment.

When it comes to protein, where it comes from matters. While processed meat may have a lot of protein, it also has saturated fats and other ingredients that are bad for you. Whenever possible, you should get your protein from plant sources. Plant sources provide not only protein but also fiber and micronutrients as well. The best plant sources of protein include: 
Beans
Lentils
Nuts
Seeds
Whole grains

If you do eat protein from animal sources, choose healthier options such as: 
Poultry
Fish
Seafood
Eggs
About 3 servings of dairy daily, particularly yogurt.