Perusall is a social annotation tool that is integrated into Canvas.
Scroll down a bit in this documentation and you can see how to get Perusall to show up in your course.
The grading (as we discussed) can get a bit fussy. But you can also have it automatically show up in Canvas gradebook. Automating your grading in that way takes a bit of planning. Consult with the instructional support team for your school to get that set up.
Ed Discussions is a discussion tool that integrates into Canvas. It can be a great place for students to ask questions and it allows for anonymity. (It is less good for graded discussions of the sort you might hold on a Canvas discussion board.)
Note that to participate in the pilot for Ed Discussions you should fill out this form.
Bill mentioned using Miro which is a whiteboard tool that the School of Design has access to but not every school does. You can learn about other whiteboard options (O365 has a whiteboard and you can use Google Jamboard).