In Canvas you can manage access to your course through the course availability dates and publishing.
The Course Availability dates, by default, are set to the your School's Term. But, if needed, you do have the ability to change the date.
Publishing material enables students to see and access that material. You will need to both publish your course material (pages, assignments,quizzes) and your class.
In Canvas, course visibility is related to the University Term dates. These dates influence when the course is visible on your dashboard, when assignments can be created, and when the course becomes viewable only to both the student and the instructor.
As an instructor, while the term is in session, you have the ability to extend the date of your Canvas course. Doing this will can provide you extended access to edit grades (Note: Final Grades should be updated in Self Service) and allow students with extensions to complete work.
To extend your course dates:
By default your course is not published. This enables you to control when you want the students to see your course.
There are two ways to publish a course