Alright kiddo, so "Hama ya" is a phrase that comes from the Japanese language. "Hama" means "beach" and "ya" means "shop".
So basically, a "Hama ya" is a type of store that you can find at the beach in Japan. It's a special kind of store that sells things that people might need or want while they are spending time at the beach.
You might find things like sunscreen, beach towels, hats, sunglasses, and even drinks and snacks at a Hama ya. They're very popular in Japan because they make it easy for people to buy the things they need so they can have a fun day at the beach without worrying about forgetting something important at home.
So that's what "Hama ya" means, it's just a shop at the beach in Japan that sells cool stuff!