Fuck Tubacain. I own a lot of his featured writings: “The Milling Machine”, etc. I also own how to run a lathe. That type of shit including tubalcains confusing weird YouTube videos on prehistoric indexing heads will leave a newbie confused off their ass. Get real.
I think tubalcains methods are just what a 16-year-old should watch/learn. A CNC router might be a good start for a 16-year-old. At 18 a job in a manual machine shop perhaps just sweeping the floor, with studying programing at home.
Computer savvy kids should catch on to programming. But machine shop does not mean slacking at school. There is some math in machining so school skills can still be important so you don't become a lifetime machine operator.
There are good machine operator jobs to be had but you need to pass an HR person who chooses according to his/her education, and every home town does not have these good jobs..so get-the-job skills are important.
A decent lathe the quality of a south bend/logan with having a mill vise might be an ok/good start.
A starting machine shop might be a lathe, drill press with a drill tap chart, a bench grinder, a good bench vise, a hack saw, a digital caliper, a set of jobber drills, and what you need to run your first projects.
*But you can kill yourself with this much/ so safety skills are important.