For online courses, security can be an important issue. You may need to have measures in place to ensure (to the best of your ability) that the people taking a course are who they say they are.
When the learners are not present to verify their identity with photo ID, it can be too easy for someone else to take the course.
Fortunately, there are WordPress plugins that can help verify a user’s identity with Two-Factor Authentication (2FA).
2FA adds an extra layer of security to your website by requiring users to verify their identity using a mobile phone or security code, in addition to entering their password when logging in.
A popular 2FA plugin is Duo Two-Factor Authentication. For information and setup instructions, see: https://www.duosecurity.com/docs/wordpress
There are other 2FA plugins available. Ensure that the plugin you choose has the ability to force 2FA for all users of your site.