You might ask "how many" in relation to countable objects, but "how much" for non-countable. For example," how much milk would you like?" Or "how many glasses do you have?"

I think the basic rule would be that "how many" is used when talking about countable objects and "how much" is used when talking about uncountable objects. "How many hours will it take for you to finish the job?" "How much time will it take for you to finish the job?" You can count hours but not time.

How much ....? = uncountable nouns For example: How much coffee do you drink? How many ....? = countable nouns For example: How many cups of coffee do you drink? Countable nouns in the singular take the article a or an and can be plural. Uncountable nouns do not take an article and do not have a plural form.