Have you ever played with a toy car that you can control with a remote? A cruise missile is like a robot toy car that can fly in the air and go really fast, and it has a remote control too. But instead of being used for fun, it's used by the military to go to faraway places and attack enemies.
The way it works is that it has a powerful engine that lets it fly for a long time and go very fast. It also has a special guidance system that can help it figure out where it needs to go, just like how your mom or dad might use a GPS to figure out how to get to the store.
But the most important thing about a cruise missile is that it has a special weapon on it, like a bomb, that it can drop on targets. This can be really useful for the military because they can use it to attack enemy bases or destroy important targets without putting their soldiers in danger.
So basically, a cruise missile is like a super-fast robot toy car with a GPS and a bomb on it that the military uses to attack enemies far away.