nurse vs care for

nurse is a noun but care for is not a noun.

Word	Noun	Adjective	Verb	Adverb
nurse	Yes	No	Yes	No
care for	No	No	Yes	No

As verbs, care for is a hypernym of nurse; that is, care for is a word with a broader meaning than nurse:

Other hypernyms of nurse include treat.

nurse (noun)	care for (noun)
one skilled in caring for young children or the sick (usually under the supervision of a physician)
a woman who is the custodian of children

nurse (verb)	care for (verb)
try to cure by special care of treatment, of an illness or injury	provide treatment for
give suck to	have a liking, fondness, or taste (for)
maintain (a theory, thoughts, or feelings)	be fond of; be attached to
serve as a nurse; care for sick or handicapped people
treat carefully