Talk to Dermatologist on Skin Tanning

Aoa. My skin color is wheatish (yellowish shade) or it can be said that it is warm tone whenever my skin expose to sun even for a day my skin gets tan very fast. I have to go to university every day. Due to today's heat my skin color has become very dark. Please suggest me a sun block and also help me by recommending the solution of not getting complexion of the skin dark so quickly. P. S: I don't have color complex I just want to have my natural color back. It gets very irritating for me for getting tan skin in a day after exposure of sun. Thanks