Here are some examples:
* "I bought a can of blue paint." (Here, "paint" refers to the substance itself.)
* "The artist used oil paint for the portrait." (Again, "paint" refers to the substance.)
* "The paint on the wall is peeling." (Here, "paint" refers to the layer of paint applied to the wall.)
However, "paint" can also be a verb, as in:
* "I will paint the house tomorrow." (Here, "paint" refers to the action of applying paint.)
So, whether "paint" is a noun or a verb depends on how it is used in a sentence.