Opening a forex trading account these days is quite simple and can be done online. Before trading, the forex broker will require a customer to deposit money into the new account as collateral.
Brokers also provide leverage to customers so they can trade larger amounts than they have on deposit. Depending on the country the trader is trading from, that leverage can be 30 to 400 times the amount available in the trading account.
High leverage makes forex trading very risky and most traders lose money attempting it.