Have you heard about MOOCS or Massive Open Online Courses?
Courses here are categorized into the following subjects: Computer Science, Mathematics, Programming, Data Science, Humanities, Social Sciences, Education & Teaching, Health & Medicine, Business, Personal Development, Engineering, Art & Design, and finally Science.
He has also written an article on signing up for Coursera courses if you need help.
Here are some programming courses, for example:
You can find the full list here.