“Any” can be singular or plural when you use it as a pronoun, depending on whether it refers to a countable noun (like “book” or “books”) or an uncountable noun (like “water”). “Any” is singular when it modifies singular countable nouns, and it becomes plural when used with plural countable nouns.

We use “any” + singular noun when we are looking for a specific piece of information or in certain positive sentences. We use “any” + plural nouns in regular interrogative and negative sentences. If I ask you any question, you will answer it for me. Do you have any questions?

When any refers to a singular uncountable noun, it is always singular. Is / are any of the information available yet? As a determiner, any is generally followed by uncountable and plural countable nouns in questions and negative statements. Is there any water left in the bottle?