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When creating an assignment, you can set up peer a built-in peer review by checking the "Peer Review" box:
You can then either manually assign participants (after the assignment is submitted) or have Canvas automatically match students together. You can also allow for anonymous feedback from one student to another.
Using peer review this way does not create a gradebook item for the review, just the original submission. If you want peer review to be graded, add a "no upload" assignment and grade manually.
Canvas Support Article: https://community.canvaslms.com/t5/Instructor-Guide/How-do-I-use-peer-review-assignments-in-a-course/ta-p/697