Yeah who needs a life anyway? So bassically it's probably going to take a super long time if I learn the hard way. So getting maps is the way to go then?
It's a good idea to start with a car that doesn't require an
x kilobucks equipment to read/write.
So if you're serious about taking this on as a career - IMO get some el cheapo ME7 equipped vehicle (preferably turbo, ofc) to practice your basics on. There's a ton of info for ME7 to get you started. Also get some proper book on ICE operation if you're shady on how it works internally.