 Publish your courses to the outside world. Your administrator must first register your site with community hubs. To do this, log in as administrator, go to the front page, settings block, site administration, registration. You can register your site with Mooch. This is Moodle's official community hub and all a specific community hub that's open to registrations. So you would go through and complete the registration information and then register when you've done so either as the administrator or under the manager role for a given course. You would go to the course concerned and publish. You will then have an option to either advertise your course on a community hub where users can then follow a link to your site to enroll in the set course or else you can share a copy of your course on the nominated community hub.