In fact, every time you pay the bill, you actually buy it at the selling price on the platform, and the list you sell is sold at the other party's buying price.
In this case, when you place an order, the platform has actually automatically deducted the cost of the spread. If the profit you earn does not exceed the spread, you will lose money. In other words, the smaller the spread, the smaller your cost, and the larger the spread, the higher your cost. Generally speaking, the spread of banks is much higher than that of foreign exchange dealers.
If you still don't understand, you can contact me and I will explain it to you in detail.