Go to Settings ❯ Apple ID ❯ Media & Purchases then sign in to your Apple ID with your password, to see ‘Account Settings’ and Manage Payments, Subscriptions, Purchase History, Add Money to Account and set the Country/Region
Go to Settings ❯ Apple ID ❯ Media & Purchases then sign in to your Apple ID with your password, to see ‘Account Settings’ and Manage Payments, Subscriptions, Purchase History, Add Money to Account and set the Country/Region