You can add your Zopa credit card to your Google Wallet in 2 ways:  

Add your card from the Zopa app.  

1. Open the Zopa app and click the credit card tab.

2. Go to Manage.

3. Tap add to GPay and follow the steps.  

Add card from your Google Wallet 

Or, you can add your card directly from your Google Wallet by entering your card number, expiry date and CVV security code. You can find these details on the back of your card.