As per the description above, you want to download the Adobe PDFPack on your computer, Is that correct?
Adobe PDFPack is an online service and cannot be downloaded as an application. But we can access the services through a browser and can be accessed through desktop and mobile app Adobe Reader DC.
Please access the services through https://cloud.acrobat.com/convertpdf with your Adobe ID and password on Chrome, or Firefox, or Safari.
You can also use the services through free desktop version of Adobe Reader, just sign in with your current Adobe ID and password in Adobe Reader, to download the Reader, use the URL Adobe - Adobe Acrobat Reader DC Distribution
For more troubleshooting, you may refer to Troubleshooting Create PDF, Export PDF, Adobe Send, Fill & Sign … services(PDFPack or Document Cloud...
Hope this helps and let us know if you need more assistance.