LIVING on a train (cooking, eating, sleeping, etc).
Cooking - food on trains is usually prepared beforehand and kept heated (or cooled) on the train in the buffet car.
Eating - Said food (mostly snacks and drinks) can be bought from the buffet car, but on longer journeys a full-course meal can be served in the restaurant cars. I've done this before and the quality of food is usually pretty great for food in transit!
Sleeping - only on stopover journeys! A lot of the long distance European trains have beds on them, I don't have any experience of them though so you may want someone else to fill you in on this.
personally-owned trains (owning your own train for the fun of it (or freelance cargo shipments??? idk) rather than working on a company's train)
I have never heard of this happening! Rail transport is an expensive business so I wouldn't be surprised if this was pretty impossible. I don't think this is much of an option!
could a single person operate a train? maybe not realistically but with enhancements/machines etc how plausible/possible is this??
Again, not that plausible. Operating a single engine is a two man job (driver and fireman), and with a whole train there also used to be a brake van (caboose in the US), and that's where the conductor and train crew work from. That's at least 4 people on a goods train (no need for a conductor), and at least 5 on a passenger train.
autopilot/cruise control????
This is a bad idea! Well, not so much nowadays, but if you're going for something period you might want to read up on that accident (that article is just an overview really) and the railroader culture of that time!
if we lived in a world that was far more spread out than it is and we didn't really have cars and stuff, and everything between cities was pretty much trains, how would train tracks work? in terms of being interconnected and stuff, and rail switches and the like (or even is this plausible at all?)
My guess is a bit like
this, but on a larger scale! It's actually quite plausible. As long as there's good administration and organisation (as well as the manpower) behind it, rail switches and such wouldn't really be much of an issue.
trains cannot TURN right?
Well, no, in the sense that the trains themselves don't have steering. However, you have not accounted for curves in the track! That is how trains change direction. Junctions are done with points, though these can cause problems and accidents if they're not managed properly. For turning trains round at a station or engine shed, turntables are used.
also in response to an ovious answer: I plan to take a steam train trip at some point. There's a local steam train ride thing that's somewhat of an amusement thing for people. I did it when I was a little kid, I remeber. I'd like to take a ride on that and spend some time talking with the crew.
Arrive at the station early and chat with them on the platform. Driving and powering a steam engine is a gruelling business and I'm sure they don't want to be questioned while working.
Bear in mind my knowledge is mostly of steam railways so don't be surprised if some of this information is a little bit out of date!