I have a question concerning the product of Crypto Currency debit cards example list found here: link
How long does the exchange from cryptocurrency to fiat take?
If I want to use the Debit Card in a store to pay, do I need to exchange crypto to fiat before I can use the card?
Or does this happen automatically in a later point in time, like PayPal does with its paying service, where the lend fiat money by PayPal is later on extracted from a normal Bank Account:
Here the Debit Card Crypto company would than lend fiat in the first place and exchange the crypto in a later point in time?
Because if not, why use the service in the first place, if you always have to put fiat money on the card?
Maybe some of you could share your experience with this service.