It is important to know which card you are buying, as older versions still circulate in some regions: What type of gift card do I have? - Apple Support (NG)

: You can send digital gift cards through PayPal or directly via iMessage on your iPhone. Types of Gift Cards

You can purchase Apple Gift Cards through several official and third-party channels:

Buying an Apple Gift Card has become much simpler since Apple unified its various credits into a single "everything Apple" card. This card can be used for both physical products and digital services. Where to Buy