If you have a Canvas course export package from someone else that you want to use in Canvas, or you have previously exported a course, you can import the course as a Canvas course export package.
Click the link below for the Canvas Guide about importing a Canvas course export package.
https://community.canvaslms.com/t5/Instructor-Guide/How-do-I-import-a-Canvas-course-export-package/ta-p/795