Bit rate is like how much water comes out of a hose. When you turn on the hose, water comes out and the more you turn it up, the more water comes out. Bit rate is like that, but instead of water, it's how much information can be sent over an internet connection.
Think of the internet like a big pipe that connects all the computers together. Just like water flowing through a hose, data flows through the internet. Bit rate is how much of that data can flow through the internet pipe at one time.
So, if you have a slow internet connection, it's like a small hose with not much water coming out. But if you have a fast internet connection, it's like a big hose with lots of water coming out. The faster the bit rate, the more information can be sent over the internet at one time, which means things like videos and music can play smoothly without buffering.