The balance on a gift card can be spent on more than one order. Gift card balances are applied to the total value of an order, which can include taxes and shipping.
When you redeem a gift card, the checkout displays one of the following options:
If the balance available on the gift card is greater than or equal to the order total, then the customer can click Complete order.
If the balance available on the gift card is less than the order total, then the customer is prompted to choose a second payment method for the balance before placing the order.
If you want to buy a gift card for someone else, then you would need to forward the gift card email to the recipient.