I can't help with videos or anything, but I'm sure people like Haynes would have general purpose mechanic skills stuff?
But I can say from experience...I've been working on my own (generally old and decrepit) cars for the best part of 20 years and the one and only surefire way to learn is to get in there and try stuff. Start small, servicing is the perfect place to start, and look up how to do each specific job as you go, or find someone who doesn't mind you looking over their shoulder while they do work. If you have the chance of hanging around with the classic car beardies, it would be very valuable experience too.
In the end the only important thing to make sure you learn, is how to work safely - how to lift a car, electrical safety and care with fumes and fluids - the rest can come with trial and error if needs be. Every DIY mechanic has broken things when they meant to fix something else, or found out the hard way how not to do a job...it's all part of it, and part of the joy when something goes well and you've fixed a problem for a tiny fraction of the cost of going to a garage.
Jon from Wiltshire - UK Mk1 1.6 Classic Red-ish
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