The proper noun Korea (a region, two countries) has the proper adjective Korean (adjective and demonym).
korean
Norway is a proper noun, not an adjective. It is the name of a country. It does not change.
Yes, it can be, used as the proper adjective for the proper noun Korea (Korean peninsula, Korean food). Korean is also a noun, for the language or as a demonym for a person from Korea.
France is always a proper noun it is never a proper adjective (what is a proper adjective? The adjective is french. I like french food
The proper adjective for Antarctica is Antarctic, as in Antarctic Circle.
Afghan
When a proper noun is used as and adjective, it is a proper adjective; for example:Ancient Mexican structures have similarities to ancient Egyptian structures.
England - and + ish = English.
The proper adjectives are:KoreanPolishAlaskanBelgianSwedishFrenchRussianCubanPeruvianIndian
Irish
English