what are forex and forex broker !!!

1-What are forex !!
The Forex (Foreign Exchange) Market is the largest market in the world. It is the market where currencies are traded. Each day, more than 4 trillion dollars are exchanged.
2-What Are Forex Brokers !!
A forex broker is an intermediary between you and the interbank. If you don't know what the interbank is, it's a term that refers to networks of banks that trade with each other. Typically a Forex broker will offer you a price from the banks that they have lines of credit and access to FX liquidity. Many forex brokers use multiple banks for pricing, and they offer you the best one available.
source :

2 https://www.thebalance.com/what-is-a-forex-broker-1344939