The ability to buy an iTunes (Apple) gift card with another gift card depends entirely on the type of gift card you are holding and where you shop. 💳 Option 1: Using a Visa, Mastercard, or Amex Gift Card
You can use them to purchase an Apple gift card at Apple.com or at authorized major retailers.
For example, the official Target GiftCard Policy and the Walmart Payment Methods Page both state that store gift cards cannot be used to buy specialty third-party gift cards.
💡 Some smaller regional grocery stores or gas stations may occasionally allow it due to register settings, but it is not reliable.