As nouns the difference between year and many
is that
year is the time it takes the earth to complete one revolution of the sun (between 36524 and 36526 days depending on the point of reference) while
many is a multitude; a great aggregate; a mass of people; the generality; the common herd.
As a determiner many is
an indefinite large number of.
As a pronoun many is
a collective mass of people.