Here are some sites where people can take free courses during the quarantine. Some of these are copied from the chatroom.
Coursera is offering free certificates for 85 courses at the moment. Some of them look interesting.
(See also the Recommended Coursera Courses thread.)
Here are more free things from Coursera:
Udemy also has some free courses:
Packt Publishing has some free workshops here:
Stanford has a free Web Security course: Stanford Web Security Course
Reddit has a free courses megathread:
Other Free Courses
If anyone knows of other free courses, post a comment below.