shop

店(みせ)	A shop, speaking generally. “I got to go open the shop now.” (The speaker can use this no matter what kind of shop it is).

屋(や)	Store – usually used for stores that only sell one thing:fish store（魚屋）, book store（本屋）, used clothes store（古着屋）, bakery パン屋. $$$

店舗(～てんぼ)	Branch of a chain store.