What might i do to get vitamin d and what is true about the sun?

Healthy diet: The flesh of fatty fish (such as salmon, tuna, and mackerel) and fish liver oils are among the best sources. Small amounts of vitamin d are found in beef liver, cheese, and egg yolks. Some mushrooms provide vitamin d2 in variable amounts. Ready-to-eat breakfast cereals often contain added vitamin d, as do some brands of orange juice, yogurt, margarine and other food products.