Estou no brasil agora como faço para pagar

Sign in to your Apple ID account page and edit / update your Apple ID details.

https://appleid.apple.com

• edit your billing addres.

or 

To change the billing address you can do (macOS & Windows OS) via iTunes

Start Music -> Click on iTunes -> side bar click iTunes Store -> go to Account (top bar) -> View Account -> Sign in -> Apple ID Summary -> Billing Address -> Edit.

or

(iPhone & iPad) Go to -> Settings -> tap your Profile -> Payment and shipping -> Change Address.

Edit the Address -> tap Done.

If you change Country or Region, you must comply with all regulations described here -> Change your Apple ID country or region -> Change your Apple ID country or region - Apple Support (KW)