art vs creative activity

art and creative activity both are nouns.

Word	Noun	Adjective	Verb	Adverb
art	Yes	No	No	No
creative activity	Yes	No	No	No

As nouns, creative activity is a hypernym of art; that is, creative activity is a word with a broader meaning than art:

Other hypernyms of art include creation.

art (noun)	creative activity (noun)
the creation of beautiful or significant things	the human act of creating
the products of human creativity; works of art collectively
a superior skill that you can learn by study and practice and observation
photographs or other visual representations in a printed publication