EntityValue
EntityValue[entity, property] gets the value of a property for an entity. Can query multiple entities or properties at once.
Examples
Query entity properties:
EntityValue[Entity["Country", "Japan"], "Population"]
(* Quantity[1.258*10^8, "People"] *)
(* Multiple properties *)
EntityValue[Entity["Country", "Germany"], {"Capital", "Area"}]
(* Multiple entities *)
EntityValue[{Entity["Planet", "Earth"], Entity["Planet", "Mars"]}, "Radius"]Please visit the official Wolfram Language Reference for more details.