lover vs doer

lover and doer both are nouns.

Word	Noun	Adjective	Verb	Adverb
lover	Yes	No	No	No
doer	Yes	No	No	No

As nouns, doer is a hypernym of lover; that is, doer is a word with a broader meaning than lover:

Other hypernyms of lover include actor, worker.

lover (noun)	doer (noun)
a person who loves someone or is loved by someone	a person who acts and gets things done
an ardent follower and admirer
a significant other to whom you are not related by marriage