I need to convert PDF to word. How do I begin? I am signed up for PDF pack

++In addition to the previous response.

You can access the service online via Adobe Document Cloud  as suggested in Using Document Cloud Web apps and services | Adobe PDF Pack

Also, you can download the desktop application Adobe Reader DC Adobe Acrobat Reader DC Install for all versions  and Sign In using Adobe ID to activate PDF Pack subscription. Here are the detailed steps- Using Adobe Export PDF 

Regards,

Akanchha