Add fonts to a Creative Cloud Library

I don't think font files are supported as objects in Creative Cloud Libraries. Traditional font files have to be installed in the computer's operating system or via a font management application installed on the computer. Font files can be packaged with InDesign or Illustrator documents to send to print shops, service bureaus, etc.

In the case of Adobe Fonts any type families added from that service won't leave any visible font files on the hard drive. The files can't be packaged with InDesign or Illustrator documents. But if someone opens an InDesign document and doesn't currently have Adobe Fonts used in the document added or installed those fonts can be automatically activated in the file opening dialog box.