How do I submit a Google Assignments LTI 1.3 file as an assignment submission in Canvas?
If your institution has enabled Google Assignments LTI 1.3 as a submission type, you can upload a file from Google Drive for an assignment. Unlike other assignment submissions, files from Google Drive are not uploaded into your Canvas user files.
Canvas accepts Google Doc, Google Sheet, and Google Slide files. You can also upload any uploaded Word (.doc/.docx), Excel (.xls/.xlsx), PowerPoint (.ppt/.pptx), and PDF files not converted to Google Docs formatting.
Note: If enabled in your account, Canvas plays a celebration animation when you submit an assignment on time. However, if you prefer, you can disable this feature setting in your user settings.
In Course Navigation, click the Assignments link.
Click the title of the assignment.
To add an existing file, click the Add files button .
To create a new file, click the Create drop-down menu  and select a file type .
You can choose from recent files, your Drive files, or upload files .
Google Drive displays only accepted file types for the assignment. Click the name of the file(s) , then click the Add button .
Click the Submit button.
View Submission Confirmation
To confirm your submission, click the Submit link.
After you submit your assignment, a message displays notifying you that your submission is processing. You can navigate away from the assignment submission page without disrupting the file upload
View the confirmation of your assignment submission.
To revise your work, edit your attachments in Google Drive and click the Resubmit button.
View Submission in Canvas
View the confirmation of your assignment submission in Canvas.