Yes, it is possible to change the settings within the Gradebook or Speedgrader to stop feedback being seen by students before you are ready. In Canvas this managed by the Grade Posting Policy. You can select a default grade posting policy for all course assignments, as shown below:
Posting policies can be set to automatic or manual, see below how they will display in Gradebook.
Anonymous Assignments: If you create an anonymous assignment, Canvas will automatically hide grades and feedback for the assignment.
Non-Anonymised Assignments: If the assignment is not anonymous and you have not set the Course to ‘Manual’ Grade Posting Policy, you will need to select ‘Manual’ grade posting policy for the assignment before you begin marking, as shown below:
Canvas Guide: How do I select a grade posting policy for a course in the New Gradebook?
Canvas Guide: How do I select a grade posting policy for an assignment in the New Gradebook?
Canvas Guide: How do I post grades for an assignment in the New Gradebook?
Canvas Guide: How do I hide or post assignment grades in SpeedGrader?
Note: If you have setup an assignment using the Turnitin Integration in Canvas and are using Turnitin Feedback Studio to mark students’ assignments, you MUST set the ‘Feedback Release Date’ to a date and time that you want your students to receive their grades and feedback. This date will also trigger anonymity to be forced off in Turnitin.
More information: Turnitin within Canvas – Staff Guide
More information: Important Information about Turnitin Assignments within Canvas
Yes. You can set up peer review assignments for students in Canvas. Students can then leave written and/or audio feedback for their peers.