I'm afraid I'll need a little clarification here. Are you wanting to save a PDF in Word format? Or convert a file in Word to PDF?
For the former, you can use the ExportPDF online service (or Acrobat). For the latter, you can use Acrobat. (Although later versions of Word have their own PDF generator.)
If you'd like to give Acrobat a try, you're more than welcome. You can download a free trial from the link I reference above.