Customers who enroll in a Program or Class with a required fee through the Enrollsy App or a public or private link will eventually reach a payment step.
Depending on the merchant account you have opted for, Customers can pay by Electronic Check (ACH) or Credit/Debit Card. Or you can enable a Pay Later option.
ACH View:

Credit/Debit Card View:

For Programs and Classes with a required fee, Customers will not be able to complete their enrollment until they have selected one of the options you allow for.
For a Customer to skip payment upon enrollment, they will need to use a Coupon Code or have an Admin enroll them as a signed-in user.
Check out this article to learn how to enroll someone as an Admin.