The following contains information on how to use Turnitin as a Student in Canvas: Student Hub. 

Note: The link above references setting up an account to use Turnitin, but our campus instance of Turnitin in Canvas is already established, and you will only need to submit a document to a Turnitin class assignment to use the tool. Due to the Terms of Use for our campus instance of Turnitin, students can only use Turnitin for class assignments.