Hello i am currently working on how to move a ball. With every tutorial I watch I get the same results even tho my teacher (unity/youtube) gets the right one. it is claiming unity doesn't have a defenition for AddForce. any suggestions?

rigidbody.AddForce(movement);

Assuming you are using Unity 5 it should be telling you that the syntax is obsolete. Use this instead:

GetComponent<Rigidbody>().AddForce(movement);

Full example here: Rigidbody.AddForce