Okay kiddo, imagine you're playing with your toy car and you accidentally knock something over and it starts a fire. Now, fires need oxygen to keep burning and getting bigger.
So, an oxygen firebreak is like a special kind of wall or barrier that gets put up to stop the fire from getting more oxygen. It's like if you put a lid on your toy box to keep all your toys inside.
These firebreaks can be made by using special materials like water or sand to help put out the fire or by cutting off the air supply to the fire. Scientists and firefighters use oxygen firebreaks to help keep people safe and prevent fires from spreading too much.