problems with check point in unity

i trying to make just one chackpoint but i cant this is my character code

 var speed = 6.0;
 var jumpSpeed = 8.0;
 var gravity = 20.0;
 
 private var moveDirection = Vector3.zero;
 private var grounded : boolean = false;
 
 function FixedUpdate() {
     if (grounded) {
         // We are grounded, so recalculate movedirection directly from axes
         moveDirection = new Vector3(Input.GetAxis("Horizontal"), 0, 0);
         moveDirection = transform.TransformDirection(moveDirection);
         moveDirection *= speed;
         
         if (Input.GetButton ("Jump")) {
             moveDirection.y = jumpSpeed;
         }
     }
     
     
     // Apply gravity
     moveDirection.y -= gravity * Time.deltaTime;
     
     // Move the controller
     var controller : CharacterController = GetComponent(CharacterController);
     var flags = controller.Move(moveDirection * Time.deltaTime);
     grounded = (flags & CollisionFlags.CollidedBelow) != 0;
 }
 
 @script RequireComponent(CharacterController)

can someone help me pleese