Welcome to content creation
Hi Beattie,
Welcome to the madhouse! Well, not quite, but it can drive you in that direction, lol.
I started in gmax which is free of course, just as Blender is.
Gmax needs TACS, Trainz Asset Creation Studio (also free) which will allow you to upload your work to Trainz and Auran. Not sure about Blender doing this or how it does it, somebody will come in and tell you I am sure as we all try to help each other.
When I decided do dump route creation I went over to gmax just before last Christmas (was it that long ago, seems like last week!) and have never looked back. I love it, it keeps me occupied and fills my days very nicely, and being retired and alone I seem to have more days than everybody else, so gmax was a Godsend.... ha ha
The hardest part in either utility will be texturing, I think we can all agree on that, and getting your head round this particular part of creation is vital. The cube or dice lesson is good for practice, and more practice and guess what, more practice, until you get the hang of it.
Ask your questions in the Content Creation section as I suspect most creators will visit there and it is p'roblem specific' rather than finding all sorts in the General section, in that it will only deal with creation difficulties. It is almost my first stop on the forum.
Good luck and lots of patience with whatever and whichever you decide to go for.
Angela