How To Remove Scars On Skin, Itching And Skin Discolouration Under Eyes?

Hi Dr! My questions are:- 1: I have some scars on my skin which happens because of motorbike accident and during football playing, how can I get cleared from this problem? 2: I have skin discoloration(dark) on the skins of my nostril and under my eye, some times I m having sneezing and itching of my eyes when exposed to dust or making my bed sheet; What is the cause and the possible treatments for the discoloration and itching/sneezing? Looking forward from you! Regards