Some places have Kiosks where you can redeem your gift card and get cash from that gift card although you might be charged a small fee to change your gift card into cash.
You can also sometimes redeem your gift cards for cash or money into your Paypal account through online websites.
Just be sure the online website where you redeem your gift card for cash is legit but most of them are.
A good legit website for redeeming gift cards for cash or discounts and other gift cards is
https://www.cardcash.com/sell-gift-cards/
Cardcash is legit and has been in business since 2009 which is 10 years now so you can trust them.