this question is impossible to answer. What is the criteria for best beach, fine sand and turquoise water with a beautiful scenery, activities on the beach, etc.?
You'll find beautiful beaches all over the world, like Hawaii and Florida's Gulf coast, Tahiti, Malidives Islands and Seychelles Islands in the Indian Ocean, Boracay in the Philippines, Joaquina in Florianopolis/Brazil, many others beaches in Thailand and Vietnam.
The Gold Coast Australia
followed by Bondi Sydney
Fiji, Hawaii, Australia, and South California.
Osage beach
Kokomo.
st barts