If you would like to add a pdf to a post and have it show up under a category on a page, these steps will allow you do that. First add the media to the site.  Click Media/Add New:

 

Then insert your pdf into the site:

 

Then create a new post.  Click Post/Add New:

 

Title your post and add the new pdf into the post.  The pdf embedder plugin will format into what is called a short code so it can be displayed on the site:

 

Choose a category:

 

Publish or Update: