My lo is on formula and he's 4 months and 11 days old, can I start cow's milk in less quantity??

Because of their immature kidneys, children under 1 year are incapable of digesting cow’s milk, which contains high concentrations of protein and minerals that will be hard for a child this age to digest. Also, cow’s milk doesn’t contain the right levels of iron, vitamin C, and other nutrients that are essential for infants. Goat’s milk is also not recommended for children under 1 year either. Like cow’s milk, it can cause intestinal irritation and anemia.