Dull in face colour? Is every fair individual smart or beautiful???! It's not possible to change the colour given by the Almighty. However, in case you have irregularities in texture and irregular skin tone, that can be looked into and corrected. Cosmetic creams will not help and may have side effects if used for long. So be careful. Instead use a sunscreen daily morning and afternoon.
Don't think fairness is the "cure" for your dull skin. If this continues to bother you then see a qualified dermatologist. Let me know if you need any further assistance in this regard. Take care.