Which app do you use? Acrobat Pro or Acrobat Reader on a Windows/Mac desktop computer or Acrobat Reader on an iPad/iPhone or Android tablet/phone? (Sorry for the confusing product names. But you asked the question in the mobile forum.)
In general, you need to choose a non-PDF source file (e.g. Word, Excel, PowerPoint) to convert to PDF.
If you want to create a new PDF document with a blank page. you can choose "Blank Page" in the desktop version of Acrobat Pro.
If you can tell us the product name and the platform or operating system, we can provide more specific information. Thank you.
I'm using adobe acrobat on my iPad. Then I signed in with my Adobe creative cloud membership (the $49.99/mo.) from inside that app. You mentioned creating a blank page on desktop, I guess that's what I want to do, but on my iPad. Thanks for the help, Michele
With your Creative Cloud membership, you will get the desktop version of Acrobat Pro for Windows or Mac but not the Document Cloud online subscription service for converting to PDF inside the mobile Reader app on your iPad.
Creative Cloud Desktop apps
Creative Cloud Mobile apps
Please note that the mobile Reader app is part of Adobe Document Cloud, not Adobe Creative Cloud.
Typically, people create original documents using InDesign or Illustrator, export them to PDF, and view the resultant PDF documents in Reader on desktop/notebook computers or mobile devices (iPad. iPhone, Android tablet/phone, Windows Phone).
The mobile Reader app does not provide full support for creating a new PDF from scratch or adding text and images. (But you can add comments/annotations, fill out forms, etc. in the mobile Reader app for free.)
Hope this helps you head in the right direction.
If not, would you try the Creative Cloud user forum or Customer Care to get answers?
Adobe Creative Cloud (user forum)