Could you please tell what exactly have you purchased?
Is it is one of the online service or the full Acrobat DC desktop version?
If it is Acrobat ,you simply need to sign in to license the application.
Launch PDF in Acrobat>File>Save as word file or Export to Word.
If it is an online service,you could either use through one of the browsers,Reader DC or mobile app.
Refer the following link.