I am surprised to read bad experiences about Udemy.com.
I’ve found it 2 weeks ago through an internet research. I bought a few courses and some others for free. I had a direct access with immediate possibility to start any courses. The free ones are not so good and were for me unuseful. I bought it to trust my own knowledges. one of the non-native English trainer is awful. but the course was for free. so whatever!