You can use avene emulsion sunscreen with spf 50 or rivella tint sunscreen by Cipla
The amount of sunscreen applied shoudj be at least one finger tip unit for face and has to be repeatedly applied every four hours till you are in day light or UV LIGHT SOURCES like laptops and even LEDS
Next Steps
For dullness seek a consultation with a nearest dermatologist
Health Tips
Start using a glycolic cream or a retinoid cream once or twice a week