Here are some examples:
* A pack of wolves
* I bought a pack of gum.
* The backpack was full of books.
However, "pack" can also be a verb, meaning to put things into a container or to put on clothes.
For example:
* I packed my suitcase for the trip.
* She packed her lunch for school.
So, the word "pack" can be both a noun and a verb depending on the context.