mileage vs distance

mileage and distance both are nouns.

Word	Noun	Adjective	Verb	Adverb
mileage	Yes	No	No	No
distance	Yes	No	Yes	No

As nouns, distance is a hypernym of mileage; that is, distance is a word with a broader meaning than mileage:

mileage (noun)	distance (noun)
distance measured in miles	the property created by the space between two objects or points
a travel allowance at a given rate per mile traveled	size of the gap between two places
the ratio of the number of miles traveled to the number of gallons of gasoline burned	indifference by personal withdrawal
	a distant region
	the interval between two times
	a remote point in time

mileage (verb)	distance (verb)
	go far ahead of
	keep at a distance