Big Clive for general how electronics works, really good at tearing down, explaining how circuits work etc https://youtube.com/c/Bigclive
I very much like the approach taken by Big Clive and Diode Gone Wild: taking apart everyday items, explaining what they do, sometimes also showing how they would make something similar themselves from scratch. I assume there are lots of other channels out there that do the same but for other things than just electronics.