I need iTunes card parchang

If you have a valid payment method on file, instead of buying or order an App Store & iTunes gift card, you can Add money to your Apple Account balance anytime, no gift card needed, see -> Apple Gift Card - Apple (UK)

Where to buy a physical Apple Gift Card or App Store & iTunes gift card: actually, you can buy an Apple gift card at many places, at an Apple Store or an Apple Authorized Reseller in your region.

See also this Apple article:  If you can't redeem your Apple Gift Card or App Store & iTunes Gift Card

If you can't redeem your Apple Gift Card or App Store & iTunes Gift Card - Apple Support

Beware of -> About Gift Card Scams -> About Gift Card Scams - Official Apple Support 

Hey there anascheema,

Thanks for reaching out to Apple Support Communities. We'll be happy to help with billing and gift cards.

If you're looking for options to purchase an Apple Gift Card, check out the following resource: Buy Apple Gift Cards - Apple

If this is not what you need help with, let us know a few more details, such as the device you're using and any errors you're running into. We'll use that information to help plan the best path to resolution.

Take care.