humans vs group

humans and group both are nouns.

Word	Noun	Adjective	Verb	Adverb
humans	Yes	No	No	No
group	Yes	No	Yes	No

As nouns, group is a hypernym of humans; that is, group is a word with a broader meaning than humans:

Other hypernyms of humans include grouping, homo, human, human being, man.

humans (noun)	group (noun)
all of the living human inhabitants of the earth	any number of entities (members) considered as a unit
	a set that is closed, associative, has an identity element and every element has an inverse
	(chemistry) two or more atoms bound together as a single unit and forming part of a molecule

humans (verb)	group (verb)
	arrange into a group or groups
	form a group or group together