Paypal is incorporated into the LMS and can be used by your learners to purchase access to your courses directly from the LMS.  If you prefer, you can also choose to use a different 3rd party merchant to collect payment from your learners using a third party’s payment system (which would be completed outside of the LMS). Once payment has been received, you would simply allow them to access your course or activity by setting up that learner with permissions to the course or activity.

You need to have a subscription in order for learners to be able to take courses.