There is usually sufficient protein when we eat enough to maintain our normal body weight. These include foods that are high in protein such as tofu, split peas, lentils, beans and nuts. The amino acids in some foods compliment those in others. Foods like leafy green vegetables, broccoli and raisins are high in iron. Green vegetables like spinach, kale, and broccoli are rich in calcium.
Soybeans are, too.
While some people think milk is the best source of calcium, the phosphorus in milk inhibits absorption of calcium. Good sources include nutritional yeast and vitamin supplements. Vitamin D helps the body metabolize calcium. Fish is a good source. You can also replenish Vitamin D by being out in the sunlight.