I want to change the country on my app store account and I am having some problems?
First you create an account for country B (the easiest way to do this is to create the account in the iTunes Store on your computer). Then when you log in to the account for country B, you will be redirected to the App Store of country B. While you're logged in to the account for country B you will still be able to use apps, music, books, etc. you purchased with the account for country A. When you want to go back to the App Store or iTunes Store of country A, you just need to log out en log in again with your account for country A.

So the short answers to you questions are:


Yes.
Yes.