I’ll start by plugging Harvard’s free courses catalog as well as Udemy
Edit: Gonna add 2 more I remembered-
Blender - I wish I had more time to learn it, but I did start the infamous “Donut Tutorial” once!
Watch Cartoons Online - Lots of good older stuff!
There’s also LibriVox for audiobooks of public domain books read by volunteers. They vary in quality but some of my favourite audiobooks are from there.
It was down at the moment I posted, I didn’t want to push more traffic until they were back online.