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!
My 55" was thrown out by a neighbor, power issues. $8 in eBay capacitors fixed it, but I did something wrong and shorted it while hanging, lost the magic smoke.
Fine. For $60 I got a new board off eBay. Still have a unit in my bedroom waiting to fix.