Describe something you learned online

I want to talk about learning basic car maintenance, which I picked up almost entirely from YouTube after getting fairly fed up with paying a garage for things that, it turns out, are genuinely simple once somebody shows you properly. I learned things like changing oil, replacing brake pads, and diagnosing the more common warning lights, mostly from a handful of channels run by actual mechanics who film themselves doing real jobs rather than just talking at a camera. It took a while to get comfortable, honestly — I'd say a good three or four months of watching videos before I trusted myself to actually do anything to the car rather than just nodding along and feeling like I understood it. The first time I changed the oil myself I watched the same fifteen-minute video about six times, pausing constantly, absolutely terrified of getting something wrong and stranding myself somewhere. How useful has it been is almost an understatement — I've saved a genuinely significant amount of money over the two years since, and there's a separate, less measurable benefit, which is that I no longer feel completely at the mercy of a mechanic telling me something needs replacing without any way of judging whether that's actually true. It's changed the relationship a bit, from total dependence to something closer to being able to ask an informed question, which for something I once considered completely outside my abilities feels like a fairly significant shift.