how to change a GameObject from another script

 [SerializeField]
     GameObject obj1;
     [SerializeField]
     GameObject obj2;
     [SerializeField]
     Script script ;
 
 
     void Start()
     {
         obj1= transform.Find("/Game/Player/obj1").gameObject; 
         script = obj1.GetComponent<Script>();
     }
 
     void OnEnable()
     {
         script.Cube = obj2;
     }
 

I want to change the "Cube" GameObject from the Script script to the obj2 GameObject, and the script above is not working. What happens is that the "Cube" GameObject(that is already not set) is not set to an instance of an object so that means that its not setting obj2 to be Cube, so any help will be much appreciated.