You can upload PDFs to a group page in Canvas.
Pages is designed to open to the front page for a group, if there is a front page selected. Click the View All Pages button to select a page from the Pages Index.
Select PDF Location
In the Rich Content Editor, place your cursor where you wish to insert the PDF document.
Browse for PDF File
Click the Choose File or Browse... button to browse your local desktop computer for your PDF file.
Choose a File Folder
Click the Files drop-down menu and choose where you would like to store the file.
Verify PDF Upload
Verify the placement of the linked file. The text will turn blue indicating that the link is downloadable.