My account is in usa but I want to enter an international credit card, but the form does not allow me. How do I have to proceed

chi45,

You must have your iTunes and App Stores set to the same country that your billing information is based in (i.e.: must use a US credit card in US iTunes and App Stores).

If you move to another country, you need to change the country of your iTunes Store, App Store, iBooks Store, and Mac App Store account. Otherwise, your credit card might not work as payment. For example, only German credit cards can be used to buy content from the German iTunes and App stores.

Can't change the country of your iTunes Store, App Store, iBooks Store, or Mac App Store account
https://support.apple.com/en-us/HT204447

Cheers,

Allen

My country is not listed.

I am closest geographically to the US, but since my country is unlisted, I am unable to enter my credit card. Is there anyway you can help??? I can't even purchase iTunes electronic gift cards, which I could then use in the US App Store.