I have brown spot in the white part of my eye , i had it for 2 years now and it starting to itch?

Benign nevus: Brown pigmentation deposits on the white of the eye (actually in the conjunctival lining over the white of the eye) are common, especially in pigmented races. Is this spot the same size over the two years you have noticed it? There are many reasons for eye itching and misbehaving spots are usually not the cause. See if it is present on an old picture. And then see your ophthalmologist.