You must mean sending crypto from Bitpay's app to the Bitpay debit card, which uses Mastercard's payment processor. The Bitpay card is
integrated with the Bitpay app so you can load the card using the money stored in your Bitpay account.
You may also be able to convert your crypto to fiat on an exchange and withdraw that to the debit card (CEX is one that can do this), but all exhanges are different and I admit I haven't done that before so your mileage may vary. In any case you should be able to top-up within the app.
