Earlier quoted context omitted.
I went from zero knowledge to changing my timing belt with the aid of the mfg manuals and YouTube videos. A general series like this really helps putting individual YT videos into context. A YT video on changing the timing belt might show me all the steps, but not how the engine internals look and what "interfering" means.
You can do many small repairs and maintenance activities without much specialised tools and equipment, but to confidently disassemble and rebuild engines, fuel and exhaust systems, body parts, driveline components, etc., requires more than a few hours of videos.
I fly paragliders for fun, but that doesn't compare at all in excitement to starting an engine where I just changed the timing belt.
I watched more than a few hours of video to do that. But it was possible to do with the help of YT videos and VW's official workshop manuals that you can buy and download from their erWin website.
I started from absolutely zero.
I've replaced the timing belt, water pump, alternator, brake fluid, master brake cylinder, removed and cleaned the air throttle body, flushed the coolant system, replaced the radiator, replaced the shocks, replaced the exhaust, removed the turbo and replaced the waste gate, used OBDS CAN software to troubleshoot sensor issues, etc.
It was a gradual process over several years. It was a lot easier since most of it was on my second car that I could just leave in its garage while I got parts or tools or watched another 10 hours of YT videos. But some of the stuff was on the curb.
If you're a software engineer and get paid by the hour, it's absolutely not worth your time if you just look at the money.
But it can be a fun hobby, and I really like knowing how the car works when it's starting to make weird noises on long distance vacation trips. Just know that it's not that hard in theory, but in practice the wrong bolt will shear off just as you have to put things back together and drive off with the car. So always have a plan B, especially if it's your daily driver and you can't just leave it for a week or two.
Having said all that, if you're interested in cars, then this video course is excellent. I paid for it a couple of years ago, and don't regret it.
So, reading my original comment and you response again, I can see how my comment came across as "it's easy to replace the timing belt, just watch a few YT videos". I agree that that's definitely not the case.