Almost every gas station is attached to some type of store, mostly convenience stores, which usually have a modest selection of quick snacks, drinks, beer, sometimes basic groceries and hot meals too. When I hear “Kiosk” I think one of those touch screens that fast food restaurants use for ordering in place of human cashiers. I guess it’s also the name of the small booths in malls (and could conceivably exist stand-alone) but I couldn’t imagine them selling anything more than e.g. magazines and hot dogs. Aka far less variety than a gas station convenience store.

Oh and “grocery shop” sounds too much like “grocery store” (aka larger and less convenient), and I’ve never heard the term “elementary store” before (sounds too much like “elementary school” — is it a place for 5th graders to shop?)