No, it was one of several options, but what I'm asking is if there is the ability to make something, does it HAVE to be made to allow you to "next turn"?
Just because I can build a scout, warrior etc, doesn't mean I should have to.
No, you don't have to build a certain thing just because you can, but you may be required to build
something. You'll be allowed to choose whatever you want to build in a full game. And very early in the game like that, you'll want to build at least a couple scouts and/or warriors anyway - early exploration is pretty important, for finding sites for your future cities and for getting free stuff from ancient ruins.
RE: your other question in the OP - units cost maintenance; they're going to add to your expenses as you build more of them. You can hover over the
icon at the top of the screen to see a detailed look at your income and expenses. While it's possible to build too many units to support financially, that's not a risk early in the game - and even if you do end up with too much maintenence, you can always disband outdated or unnecessary units to decrease those costs.
RE: Other advice - for map types, I'd stick with standard or small size, so you can play quicker games at the outset. (Nothing wrong with going larger, but that'll mean more enemies.) Settler or Chieftain difficulty are designed for beginners. Map type can vary; in general the AI is better at Pangea maps than Continents or Archipelagos (it has a hard time with naval transport and combat) but on low difficulty settings you'll have a good chance on any map type, really. Just play a few different ones to see what you enjoy.
Good luck with it - keep us posted. And welcome to Civilization and CFC.