genealogy vs kin group

genealogy and kin group both are nouns.

Word	Noun	Adjective	Verb	Adverb
genealogy	Yes	No	No	No
kin group	Yes	No	No	No

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

Other hypernyms of genealogy include clan, kin, kindred, kinship group, tribe.

genealogy (noun)	kin group (noun)
the study or investigation of ancestry and family history	group of people related by blood or marriage
successive generations of kin