A course marketplace is where multiple authors are allowed to create and sell their individual courses. The students can become a member of the website and then register for multiple courses, as per their areas of interest.
In a course marketplace created using LearnDash, multiple instructors can be added using the ‘Instructor Role’ add-on. They can create, manage, and sell their courses and earn a fixed percentage commission as per the number of students enrolling in their course.
This functionality can be extended to a wordPress multisite setup as well, where the Admin creates multiple sites based on author, subject category, relevant courses, and other classifications.