Vietnamese is the proper adjective for Vietnam.
Someone from Israel is called an "Israeli".
The proper adjective for the proper noun Italy is Italian.
Portuguese is the proper adjective for Portugal.
The proper adjective for Germany is German. The word German is also a demonym for a person from Germany, or for the primary language of Germany.
Germanic is the proper adjective related to the German language.
Lebanese
Iraqi is the proper adjective for Iraq.
Mexican is the proper adjective for Mexico. It is also the noun (demonym) for a native or resident of Mexico. In Spanish, the adjective form is mexicano and is not capitalized.
The proper adjective for Nepal is Nepalese, as in Nepalese mountain ranges.
The proper adjective is Colombian.
France is a proper noun. French is a proper adjective.
The proper adjective to describe someone or something from Ireland is Irish, a proper adjective.
Pakistani is the proper adjective for Pakistan.