old vs age

old and age both are nouns.

Word	Noun	Adjective	Verb	Adverb
old	Yes	Yes	No	No
age	Yes	No	Yes	No

old (noun)	age (noun)
past times	how long something has existed
	a time of life (usually defined in years) at which some particular qualification or power arises
	a late time of life
	an era of history having some distinctive feature
	a prolonged period of time

old (adjective)	age (adjective)
of long duration; not new
(used especially of persons) having lived for a relatively long time or attained a specific age
skilled through long experience
(used for emphasis) very familiar
excellent
just preceding something else in time or order
belonging to some prior time