Trying to make an enemyAI and have a few issues could I get some help?

here Is my code I could really do with some help!

 var Distance;
     var Target : Transform;
     var lookAtDistance = 25.0;
     var attackRange = 15.0;
     var moveSpeed = 5.0;
     var Damping = 6.0;
     
     function Update ()
     {
         Distance = Vector3.Distance(Target.position, transform.position);
         
         if (Distance < lookAtDistance);
         {
             GetComponent<renderer.material.color=Color.yellow;
             lookAt();
         }
         
         if (Distance > lookAtDistance);
         {
             renderer.material.color = Color.green;
         }
         
         if (Distance < attackRange);
         {
             renderer.material.color = Color.red;
             attack ();
         }
     }
     
     function lookAt ()
     {
         var rotation = Quaternion.LookRotation(Target.position - transform.position);
         transform.rotation = Quaternion.Slerp(transform.rotation, rotation, Time.deltaTime * Damping);
     }
     
     function attack ()
     {
         transform.Translate(Vector3.forward * moveSpeed * Time.deltaTime);
     }