Learn to work on a car, but how?

Hi everyone, I'm currently driving a Mercedes CLA (as a company car) and since it's running out next year I'm already thinking about what to get next. I'd love a classic or modern car, like a VW Beetle, FIAT 500, etc. My dream would be to buy the car and cruise around in it in the summer and then have a car that will get me through the winter :D. The only biggest problem is that I'm a machining mechanic and not a car mechanic. In short, I have no idea about tinkering. I'd like to learn, but I don't really know how. Do you have any tips?

Thanks for all the answers 🙂