Anywhere between Panama City Beach to Pensacola Beach features the pure white sand beaches the Florida panhandle is famous for. I-10 runs inland from the coast with Panama City Beach the most distant off I-10 and Pensacola Beach the closest to I-10.
Personal favorite: Destin/Sandestin
Leave I-10 at Defuniak Springs southbound on US 331 until you get to US 98. Then head west into Destin, Okaloosa Island and Fort Walton Beach. All very, very impressive.
BobK/Orlando