Exchange means when one person buys and another person sells. So unless you trading OTC exchanges every "Bitcoin exchange" has a similar market style buy-sell mechanism. It means that Binance merely provides you a marketplace to buy/sell your securities. So when you buy an altcoin seeing it's market price. That market price is the price of the most recent altcoin sold or the most recent transaction you can say. When you place an order at the same price by setting a limit order of that price. It just means that you have picked up a commodity from the shelf and put it into your shopping cart but you will only buy it if the person selling it is going to sell it at the price you have determined. Similar mechanism takes place at the seller side it's just the opposite. So where these both points create an equllibrium is the point where your trade takes place.

It's absolutely different from buying something using card.

Remember if you use the 'Market Order' option on the exchange it would buy the stock on whatever price it's available even if it's higher or lower than the market price. Price changes every mini second depending upon volume of transactions.