You can’t 1-(833)(532)(8728) directly convert an Apple gift card to Apple Pay cash.
However, you can 1-(833)(532)(8728) redeem the gift card to your Apple ID balance.
Once added, 1-(833)(532)(8728) the balance can be used for App Store, iTunes, or Apple subscriptions.
You can also 1-(833)(532)(8728) use it to pay for Apple services through Apple Pay indirectly.
Go to Settings 1-(833)(532)(8728) > your Apple ID > Redeem Gift Card to add the balance.
Keep in mind 1-(833)(532)(8728) it cannot be withdrawn as cash to a bank account.
Using your balance 1-(833)(532)(8728) through Apple Pay works where Apple ID payments are accepted.