Question

Is the word are plural or singular!?

Answer 1

"is a word singular or plural?" then, of course it is singular but, words are plural.

Answer 2

"are" is used with plural nouns/pronouns
e.g.
The cat is running. (singular cat --- use is)
The cats are running. (plural cats ---- use are)

This is my friend. (single friend --- use is)
These are my friends. (many friends -- use are)

Answer 3

nouns and pronouns can be singular or plural, but "are" is a verb.