@Sphinx It's simple: "Greece" is the noun, meaning the country. "Greek" is the adjective, meaning people or things that come from this country.

examples:
I come from Greece, so I am Greek. I live in Greece as a Greek citizen.
I like Greek cheese./This cheese is made in Greece.

Fun fact: In the Greek language we don't call ourselves that! 😂 "Greece" is "Ελλάδα" (Hellas) and "Greek" is "'Έλληνας"/"Ελληνικός" (Hellenic).

@gioypi

Thank you, I need to work on my English more.😊
I guess the same as French and France.

@Sphinx Yes, exactly the same.