Once grades and feedback have been released by your teacher, you can access them from the Final Submission page in the Student Environment.
This article covers accessing feedback depending on the marking tool your teacher has used:
Turnitin Feedback Studio
You’ll see your grade from Final Submission page, and then be able to click View grades and feedback to review the marked version of your work in Turnitin Feedback Studio.
In Feedback Studio you’ll be able to see your work along with any comments, marks, or rubrics your teacher has used for marking. Learn more about viewing feedback in Turnitin Feedback Studio.
Canvas SpeedGrader
If your teacher is providing feedback through Canvas Speedgrader, you'll be able to access it from the Final Submission page in the Student Environment. Just click View feedback in Canvas to be directed to the right area in Canvas.
You can find more information about reviewing your grade, comments, or rubrics in Canvas in this article.