As a die hard Jack Of All Trades handyman, I can't overstate how incredible a resource YouTube has been for me. You need to come at it with at least a small baseline of knowledge of what you're trying to attempt, good shop hygiene/safety habits, patience, a "measure twice, cut once" attitude, and so on. But once you get in the right mindset, there is just so much to learn there. I credit online resources for helping me to learn:

Basic carpentry. I've built several pieces of furniture around my home including a pretty nice poker table (so, upholstery too). I built a 12'x6' shed in my back yard on a foundation that's not going to sink or slide over. Drywall and ceiling repair. Re-did a bunch of baseboard trim and only me and someone who knows what they're doing can find the mistakes. I know my limit though. I'm probably not going to attempt kitchen cabinetry or replace my roof for example.

Basic plumbing. Gutted and replaced bathrooms and kitchens on multiple houses. Repaired a busted spa back to like new. Re-did sprinkler systems. Cautiously working my way up to gas lines--don't want to blow up my home.

Basic car maintenance and repair. Everything from oil changes, brake pads up to replacing intake/exhaust systems, replacing a power steering system, light bodywork.

Metal and fiberglass work. I'm building a single engine kit plane in my garage. Online resources have been vital, and there's no way I'd have gotten anywhere on this project without them.

You need to have a good filter. You're right that the highly polished "Brought To You By Tool Company!" productions with the generic 80s porn music soundtracks are pretty bad, and the "Hey Guys! Like And Subscribe" bros are always the worst. Find the videos without background music and with bad lighting and sound quality where the person is actually grunting and doing the work in real time along with you. They're usually the best.