That depends on the type of gift card you cashed out.
Visa Rewards
Visa Rewards cards do not have a PIN. The 3-digit code on the card is a CVV (Card Verification Value), not a PIN. When using your Visa Rewards card to make a purchase, always select Credit.
All other gift cards
Other gift cards have a PIN. You can find it by clicking the link in the email you receive after your cash out request is processed.