The app is limited to what you can do on it, you would need to go on a web browser to change the country, you can't get it in the app. When you're in the web browser on your account, if you go to account and settings you will be able to change it in there.
You have clicked a link to a site outside of the QuickBooks or ProFile Communities. By clicking "Continue", you will leave the community and be taken to that site instead.