Hulu
Disney+
Youtube
A few Amazon Prime video "add-on" channels
Github
Brilliant
Patreon - I support Professor Leonard, Lost In Vegas and 3blue1brown
ACloudGuru
Lynda
Pluralsight
Egghead.io
I also have a membership at the local hackerspace (SplatSpace) even though I haven't been going to any physical meetings or really using the space much since COVID.
Probably a few more random things I'm forgetting.
As someone who struggled with Math in school I've considered using Brilliant to bone up. Have you found it useful in that regard?
In your case I would start with Khan Academy - they have material from kindergarten level all the way up to undergraduate university level so you can pick things up from where you feel most comfortable. And Sal explains things in a very human way which is nice for people who have struggled with math before.