Okay kiddo, so there's something called "carbon" which is a type of element that's found in lots of things around us. When you breathe out, you actually breathe out carbon dioxide, which is a gas made up of carbon and oxygen molecules.
Now, sometimes people use the word "carbon" to talk about how much of this gas is being released into the air. For example, when cars or factories or other things burn fuel, they release carbon dioxide into the air, and that's not always a good thing.
So people might talk about trying to reduce their "carbon footprint," which means using less energy or producing less carbon dioxide. This can involve things like driving less, using energy-efficient light bulbs, or even eating less meat (because raising animals can also release a lot of carbon dioxide).
Overall, the goal is to make sure we're not putting too much carbon dioxide into the air, because too much of it can cause problems like climate change. So it's important for us to be aware of our carbon usage and try to reduce it whenever we can.