Since you seem to know a bit can you set which countries/regions have access say something like "only north america and Africa" ? Not an apple dev so I don't have a clue.
Yes. You can include or exclude regions and individual countries.
Another interesting thing: Apple’s price tiers are anchored to the US dollar. Even though I am a German developer, selling only to German speaking people in the EU, I have to adjust my price tier if the USD/EUR exchange rate is changed by Apple. They check for this roughly once per quarter.