im making a simple shove each other off the Cliff game how do go about making a scrips that adds force pules on enter collision
A good place to start would be to check out Rigidbody physics.
That is part of a series on physics. with rigidbodies you can add force, manage collisions, add colliders, and all sorts of useful stuff!
This should help you
void OnCollisionEnter(Collision collision)
collision.collider.GetComponent().AddForce(new Vector3(your force), ForceMode.Impulse);