Not anymore. In the years 2012-2017 platforms like coursera or edx provided full courses for free, including graded assignments and exams, teaching assistants hours in the form of discussion forums, and even completion certificates.

From around 2017 these platforms started limiting free access, so now in most cases you can only see the lecture materials, with no access to assignments. From watching alone, learning is incomplete for many people.

In addition, many high quality courses (by MIT, Stanford, Berkeley, Caltech, etc.) disappeared from the coursera and edx platforms.