how do i get my apple card working

To add an existing Apple Card (after approved application) to your device follow the following page:

How to add Apple Card to your Apple devices - Apple Support

For general setup for the Apple Card see here:

Set up and use Apple Card on iPhone (U.S. only) – Apple Support (AU)

To Apply for the Apple Card please see here:

How to apply for Apple Card - Apple Support

Apply for Apple Card on your iPhone

1. Open the Wallet app and tap the Add button .
2. Select Apple Card, then tap Continue.
3. Complete your application.
4. Review and agree to the Apple Card Terms & Conditions.
5. Accept your offered credit limit and APR.3

After you accept your offer, Apple Card is added to the Wallet app and you can request a titanium Apple Card.

To apply on your iPad, open the Settings app, scroll down and tap Wallet & Apple Pay, tap Add Card, then select Apple Card.