In your course, click the 
button:
Select the Invite Learners tab to invite your learners to this course.
You have three options:
Manage Users
Add users or groups to the course. The users and groups must be created on the platform.
Invite by email
List the email addresses of your learners (comma separated) and click Send. The learners will be sent an email inviting them to self-register to the platform and join your course.
Invite with link or QR
Send the link or QR to your learners. When they click on the link or scan the QR code, they will self-register to the platform and join your course.Note that anyone with the link can join your course.