Instructors have the ability to merge multiple course sections into a single “combined” course, and instructors who have multiple sections of the same course will notice this has already been done for them. Canvas calls this functionality Cross-List and you can read up on how to cross-list or de-cross-list courses from the Canvas Guides links below.
How do I cross-list a section in a course?: For creating a combined course.
How do I Separate Sections use the De-Cross-List Tool?: For separating courses that were automatically combined based on the course schedule.
Note: Once you de-cross-list a course, all grades and student submissions are removed from the course. If you need to retain student grades, you should export the Gradebook and import it into the de-cross-listed course.