I don't think you understand the idea behind a blank slate character.
Blank Slate Characters are supposed to be entirely your creation. There backstory, past, what they know, what they don't, where they've been is entirely up to you. There is no canonical backstory for the Courier, there's what you choose to be the backstory for
your courier.
When you have the option with the Lonesome Drifter to say "Idaho, you aren't 18 are you?", that doesn't confirm the courier slept with a woman in Idaho, it's just a suggestion on a certain piece of information to add to your courier's backstory if it suits them. If you do not think a certain dialogue option suits your courier, you don't pick it.
The same can be assumed of the questions about what the NCR is. If your character doesn't know about the NCR, pick those options, if your character knows all there is to know about the NCR, choose different options. New Vegas has very few mandatory backstory options, and the dialogue is optional solely if it suits your character.
- Sunny Smiles: But maybe that's just something folks in the NCR cooked up to make themselves seem more useful here. Less uninvited.
- Courier: NCR?
- Sunny Smiles: The New California Republic. Bunch of settlers and soldiers coming in from the West, fixing on making Nevada their own.
There is also the following unused but voiced
dialogue with Lieutenant Hayes:
- Courier: What's the New California Republic?
- Lt. Hayes: Where do you come from that you haven't heard of the NCR? Nevermind, it doesn't matter much. If you haven't heard of us, you must not be from the Legion. Put simply, the NCR is the greatest nation currently functioning.
You realise those are
optional dialogue options, not mandatory right? The Courier is not one established character, it is whatever character of whatever backstory the player decides.
Those options are included there for players new to the game so they can learn about the backstory. They are entirely optional and you have no obligation to choose them if you don't want to.
If you want to play a Courier who knows about the NCR don't choose those options. How much the character knows is entirely up to you, since it's your character.
Not every Courier asks those questions, and it's up to the player to decide whether there character would know that or not.
The Courier had to deliver packages directly from the NCR and traveled all around NCR territories. Certainly, there would be some knowledge of what the government was like.
The only confirmed places the Courier has been are Primm, Goodsprings and The Divide.
Everything else is optional.
Also, unrelated, but your posting style really reminds me of that of Brycen. The way you separate quotes via the [...] is very similar. If you are him, I'd recommend sticking to one account, having alts is against the rules.