That may not be possible, depending on the PDF and the actual format you are looking for. In general, Avery supplies MS Word templates, which you then print (or convert to PDF). If you are dealign with a label page that contains multiple labels, and your PDF file only contains one copy, you would need an imposition application to copy the information to a target page that multiple times, while making sure that the location of each copy falls on a label.
If you already have multiple records of data in your PDF file, but the data does not align with the labels, it gets even more complex. I would probably come up with a way to extract each data record into a separate PDF page, and then use imposition software to assemble the final page.
If that still does not answer your question, we need a bit more information about what your PDF file looks like, and what type of label stock you are planning on printing on.