You can select the Revolut card you wish to set up in Apple Pay directly from the Revolut app. In the app, go to the 'Cards' tab to select your card. Find the card you wish to add and click the 'Add to Apple Wallet' button.
You can also enter your Revolut card information in the Apple Pay app. In this case, there may be a temporary authorization hold, which may take up to 15 days to refund.