If your course is still in development, there is no need to delete it, as courses in development have not yet been launched. Only people with a direct link to your course can see it.
If you would like to remove a course regardless of who can or cannot see it, you can delete the repository on GitHub. This will completely remove the course from the DataCamp system. Note that this action cannot be undone.
Note: Someone with a link to a deleted course will encounter a 404 error message.