What interesting free and low cost things can do you online?

[ConfusedandContrary]

I'm trying to create a list for a friend who is confined to bed for the foreseeable future. She loves to learn so any particular YouTube channels or sites where you can do anything interesting would be wonderful. I've directed her towards the many radio plays and audiobooks on YouTube which she's enjoying but there must be many other things to do online that I haven't considered.

Any ideas would be welcome. TIA

Oh, I've just started listening to the Imagined Lives podcast. Each 45 minute episode tells a story of a famous person before they were well known. You don't find out who they are until the end. It's really good.

Thank you Wobytide. I think she'd find that fascinating and she'll really love that podcast, LegoCardSwapper(as would I.)

What about downloading some Podcasts? I particularly love listening to the Dessert Island Discs podcasts!

I second looking into Openculture.com. It offers more than 1300 free audio and video courses in subjects from the brain to Linux to European history from world famous universities. There are also 800 MOOCs. Oh, just check it out. And there's Khan Academy. And podcasts--just google "best podcasts 2019" to get a list of things you might love.

Readly isn't free but it might be worth it if she is out of action for a while.

Loads of free online courses. The Open University has many, so do some other unis.
Ted Talks
There are some great How To videos and workshops on line, from starting up a business to self publishing on Amazon.
There are quizzes. I used to enjoy doing the life-audit style quizzes which help you think about what you want to do next in your life.

FunTrivia
I have been a member here for over ten years now, and I love it.
It's free to join, or you can play as a guest, then if you like it you can pay for gold membership, but you don't have to.
I have written over 300 quizzes on there too - there is loads to do, and it's generally a really nice community too.

Thank you so much to everyone who has posted since my last reply. I'm very grateful to you all for these wonderful ideas.

Sorry to lower the tone, but there is plenty of high quality fanfiction (and terabyte upon terabyte of bad stuff) if she wants some less demanding reading...