Open edX is best platform for e-learning. Open edX is python based MOOC platform.
i have more than 4 years of experience in edx, i have worked on 20+ open edX project.
i have seen your requirements for Open Edx learning platform. Yes, Open edx used for online elearning same like coursera. Student needs to pay for paid course and on course complete he/she will get certificate.
Open edX provide two application 1) LMS(learning management system) for students to enroll into course and start learning.2) Studio(Content management system) for instructor to create and manage course content.
There are also admin panel to manage students, courses and other details.
Open edX providing different types of components like audio, video, PDF, Html, quiz, timed exam, scorm etc. Open edx also provide certificate on course complete.
Open edX is more better than to other platforms because of it's user friendly, easy to maintain, scalable and open to customise. It's also providing native mobile application for android and IOS which is big advantage of this platform.
i have worked on open edx different versions, i have expertise in installation, themeing, payment gateway integration, better server architecture for more concurrent users.
For this platform set you need purchase cloud server, I'll do other things like installation, setup by myself. I can also suggest you best server architecture.
I can show you demo. Let's discuss in inbox about more details.
Thanks