How to create an iTunes Gift card code no. Please tell me.

You cannot "create" a code. Only Apple creates such codes. You need to buy or be given a prepaid iTunes card or an iTunes gift certificate to get a code you can redeem in the iTunes Store. Such cards and gift certificates are not available in all countries, and if Apple does not offer them in your country, there will be nothing you can do.

Regards.

What do you mean 'how to create an iTunes gift card code number' ? If you've bought a gift card then the number should be on the card, or if somebody has sent you an emailed gift then the code should be in the email.

You don't need an iTunes gift card number, the field is optional

How change iTunes gift coad

Follow these instructions : Change your iTunes Store country or region - Apple Support

What do you mean 'change' it, what exactly are you wanting/trying to do ?

Hi sir before I'm useing the phone Singapore now I'm stay in India how Chang app st

I don't know coad num