How To Make Ammo & Realod for Gun & Spark for Gun ?

Hi guys

how to make ammo in my script and make GUI of ammo like this : 30/270 & make realod for gun

this is my script :

     #pragma strict
      
     var Effect : Transform;
     var TheDammage = 100;
     var shotsPerSecond = 8.0;
     private var timestamp = 0.0;
     var ShotSound : AudioClip;
      
     function Update () {
      
     var hit : RaycastHit;
     var ray : Ray = Camera.main.ScreenPointToRay(Vector3(Screen.width*0.5, Screen.height*0.5, 0));
      
     if (timestamp <= Time.time && Input.GetMouseButton(0))
     {
     if (Physics.Raycast (ray, hit, 100))
     {
     var particleClone = Instantiate(Effect, hit.point, Quaternion.LookRotation(hit.normal));
     Destroy(particleClone.gameObject, 2);
     hit.transform.SendMessage("ApplyDammage", TheDammage, SendMessageOptions.DontRequireReceiver);
     timestamp = Time.time + 1.0 / shotsPerSecond;
     }
     audio.PlayOneShot(ShotSound);
     }
     }