Louis Rossmann, Jessa Jones, these are all people I'm aware of at least on YouTube that are people who truly care about teaching the public how to do a lot of their own repairs.
I can tell you, I'm a software guy. And I was absolutely intimidated by circuit boards, until I found the world of electronics repairs on Youtube (EEVBlog too). Now I have fixed two power supplies and a pair of headphones. In all those cases, I was able to get parts easily from third parties (and for my headphones, I got cheap replacement parts from AudioTechnica themselves).
I am delighted to have rediscovered this part of my skills that I lost in my teens when I fell in love with software development.
Yet I still can't get a genuine apple battery to replace on my phone. I've successfully replaced batteries on about 5 iPhones now, but they were all shady battery replacements on Amazon. Frankly I'm just annoyed that Apple doesn't make these parts available.
Look at the backlog for battery replacements now. If you get it from Apple, there is now a monthslong wait-list at the genius bar because they've created their own bottleneck.