In this video, I go through how you can use AutomatorWP along with LifterLMS to auto-enroll all users who register to your website into a specific course upon registration.

The AutomatorWP tool works a lot like Zapier where you have automations that have triggering events and actions.

The free Automator tool does allow you to have auto-enrollment, but they do have a paid version that also offers a lot more functionality on top of that: https://wpcourseguide.com/go/AutomatorWP