Very related to Countable and Uncountable nouns. Now, I'm going to cover the topic of 'quantifiers'.
But first of all: what are quantifiers? Well, these are specific words or phrases that we can use with countable and uncountable nouns to refer to an amount/number.
I know that you want to understand this better, so for this occasion, I'm using Karina to explain:
Karina is a tortoiseshell cat. She's very special because she, technically is a black cat, but she has some beautiful colours as she had absorbed some sun rays.
As you can see in the picture, it says 'a lot of colours'. On a similar wavelength, I say 'some colours'. The reason behind this is because, although colours can be counted, we can talk about them as groups. Yeah! That's pretty cool, isn't it?
Those are examples of quantifiers. You can use them for cases like this one, but you have to be very careful because there are quantifiers you can exclusively use with countable or uncountable nouns only.
Quantifiers for uncountable nouns → much, a bit (of), little, a great deal of, a large quantity of, a little, very little, a large amount of.
Quantifiers for countable nouns → many, several, few, a few, very few, a large number of, a number of, a majority of, a great number of.
Quantifiers that can be used with both countable and uncountable nouns → all, enough, none, no, some, more, most, lots of, less, least, plenty of, any, not any.
If you have trouble identifying countable from uncountable nouns, you might want to take a look at this post.