Drinking milk is good for your health and can help strengthen your bones but drinking milk will not whiten your skin.
I drink a lot of milk daily and it never whitened my skin but the milk can make your skin healthier and your body healthier as well.
So you can benefit from drinking milk often but your skin will not whiten but it may turn slightly yellow which is good for helping your skin whiten though with other skin whitening products.
Your skin does get a better glow to it though when you drink milk but you won't have perfectly whiter skin just by drinking milk.
Milk is good for bones because milk is a good source of calcium and vitamins which is very healthy for you.
I drink a couple glasses of mil everyday especially in the morning with breakfast.