Re:" I want to send Apple Pay to a friend who has an Apple phone".
Apple Pay is generally for merchants who display the Apple Pay logo or symbols
You can use Apple Pay to make purchases in stores, on participating websites and in apps.
Apple Cash can be used to send and receive money to friends but is only available in the U.S. on eligible devices
Also, it seems Apple Gift cards can only be used in the same country in which they are purchased.
( Beware of gift card scams.)
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Re: "in Dubai, my friend said you have to have a credit card to set up an Apple account?"
You can generally set up an Apple Account without a credit card by choosing "None" as your payment method,
or by using an Apple gift card to establish an Account balance:
See: How to create a new Apple Account - Apple Support
or what to do:
If you can’t create an Apple Account or see “your account cannot be created at this time” - Apple Support
You can also check which payment methods Apple can accept in your country or region:
Payment methods that you can use with your Apple Account - Apple Support
Eg: says:
United Arab Emirates