How would that be exactly work as a method of payment? How is bitcoin used in transactions today?
There are two types of bitcoin debit cards, direct pay and pre pay.
(1) Direct Pay - is where the debit card is linked directly to your bitcoin wallet. When you make a purchase, the amount is converted into bitcoin and deducted from your wallet. The merchant gets paid in fiat. This allows you to keep your bitcoin as bitcoin until the point of sale.
(2) Pre Pay - is where you load the debit card with an amount of fiat, which has been drawn off and converted from your bitcoin wallet. This would allow you to maximize the exchange rate you get for your bitcoin.
I can share videos or comparison site links if you want.
Consider using a card that advertises bitcoin, that has a reference to bitcoin on the card...we should be promoting bitcoin as much as possible!!!