How do I import work from one course to another?
Are you talking about importing work a student has done from one course to another? If you are, I'm sorry to tell you that the answer is there isn't a way to do so. The would would have to be manually copied or re-entered into the other course.
If you're talking about content from one course to another here is some documentation for you on how that's done.
How do I copy a Canvas course into a new course shell?
Retrieving data ...