How can hide game object in unity?

To make a gameobject invisible you can disable its renderer component. If you dont need the object in the scene right now (including script functionality) you may also just disable the entire gameobject.

public GameObject OBJECT1;
void Update();
{
// Collision/Way to Trigger.
OBJECT1. SetActive(false);
}
}

https://www.c-sharpcorner.com/forums/in-unity-3d-how-can-you-hide-gameobject

Hide button unity Code

GameObject button;

void Start() {
    button = GameObject.Find("Button");
}

void ButtonClicked() {
    button.SetActive(false);   
}