As shared above, that you don't need to download it. Adobe PDF Pack is an online service of Document Cloud PDF service which can be accessed from any web browser.
Refer to the steps mentioned below-
1- PDF Pack is an online service that you can use online via: https://cloud.acrobat.com/exportpdf
2- You can also use the services through free desktop version of Adobe Acrobat Reader DC: Adobe Acrobat Reader DC Install for all versions
3- “Sign In” using the email (Adobe ID) under which you have subscription registered.
4- For detailed description of how to use the PDF Pack service, you may refer to- How to Use Adobe PDF Pack
You may refer to the following link for any troubleshooting: Troubleshooting Create PDF, Export PDF, Adobe Send, Fill & Sign … services(PDFPack or Document Cloud...
Let us know if it still doesn't work.