If Assignment Enhancements is enabled in your course, you can view an assignment to verify your assignment submission.

All file submissions also appear in your personal unfiled folder.

Notes:

• If the assignment you are accessing displays differently, Assignment Enhancements may not be enabled in your course or your instructor may not have used a supported assignment type. Please view this guide for more information.
• The Assignment Enhancements - Student feature option does not support the following assignment types: No Submission, Group Assignments, Peer Reviews, and Cloud Assignments.

Canvas tutorial below:

https://community.canvaslms.com/t5/Student-Guide/How-do-I-know-when-my-assignment-has-been-submitted-in-a-course/ta-p/416678