Follow these steps to add your card to Google Pay:
Open the "Google Wallet" app.
At the bottom of the screen, tap the "Add to Wallet" button.
Select "Payment card." You will see all the cards saved in your Google account.
Choose "New credit or debit card."
To add the card, use the camera or tap the "Enter details manually" button.
At the bottom, tap "Save and continue.
Read the issuer's terms and tap "Accept."
If prompted to verify your card, choose between mobile and email verification, depending on what's more convenient for you.
To see if Google Wallet is available in your country, check here.