Uncountable nouns are confusing to many English language students. Uncountable nouns are nouns that you cannot separate into individual parts. You cannot count them. For example, you cannot count milk.
We use "some," "any, "much," and "a little" with uncountable nouns, but we don't usually use "a," "an," or "the" with them. We can say "a little milk," but we cannot say "a milk."
Here are some helpful words that go with uncountable nouns if you want to be able to "count" them. For instance, you can say the following:
a liter, gallon, carton, bottle of milk
a loaf of bread
a piece of bread.