What do you think work is? You might think that taking a test is work. But scientists have something very specific in mind when they use the word "work." Work is what is done whenever a force makes an object move some distance.
A force is a push or a pull. A force can cause an object to move that was standing still before the force acted on it. A force can change the way an object moves.
Changing the direction of the force can make the object move in a different direction. You can also change the speed of an object. You can make an object move faster by using more force.