Mandating watching a whole video isn’t a feature that’s built into Canvas but you can encourage course participants to fully watch it by testing their knowledge. After the video in a course module you can place a quiz to act as a learning check. Then you can assign a passing score that’s required to open the next module. To add a passing score from a quiz to be a module prerequisites, edit the module and go to the requirements and prerequisites area.
See the How do I add requirements to a module Canvas Community article for more information about adding prerequisites for unlocking a module. See the Modules Overview video for more info about how course modules opperate.
Here’s some information about editing questions in a Canvas quiz or in a question bank. Storing questions in a question bank becomes useful if you want to import/export questions to several similar courses.
See this Quizzes Overview video for more information about quizzing in Canvas. You can also use a series of quizzes to assess the participant’s overall knowledge of a course. Scores for quizzes and other assignments are stored in the course gradebook. See the GradeBook Overview for more information.