If you want to duplicate a course that you've created in the past then you can do that quickly and easily within the Member App software.
Find the course that you want to duplicate and select the 3 dots dropdown beside the courses name.
Your course has now been duplicated and is automatically set to 'Draft'.
You can now rename your course, edit your duplicated course and then save your changes.
To publish your duplicated course then navigate to the 3 dots dropdown again and select 'Publish'.
You both courses are now published.