Yes, you can! Combining your sunscreen with Vitamin C serum will not only double-protect your skin but also make it better with every use. It will help reduce the appearance of fine lines, acne scars, and also reduce the formation of sunburn cells and Sunscreen from ThriveCo is best as it not only protects from harmful UVA and UVB rays but also provides protection from Blue light emitted from smartphones ,laptops, computers . Yes, you can use a suitable compact after applying a sunscreen.