Access to a course is granted by adding a person to the student profile. This access is granted through purchase or manual addition, and the start date and "Start Learning" button are configured separately.
A student pays for or receives access to the digital course product and immediately appears in the outline. Alternatively, the administrator adds them manually in the Students tab. The student (or the start scenario) then starts the training—see How does the "Start Training" button work?
Customers are viewed in the product register, and students are viewed in the Students tab of the course: these are different screens.