How do I make different gameobjects appear, every time you click the GUI.button?

You just need somet$$anonymous$$ng like that bro:

 public Texture2D picture1;
 void OnGUI(){
 if(GUI.Button(new rect(50,50,50,50), "Click me!")){
 GUI.DrawTexture(new rect(Random.Range(min,max), Random.Range(min,max), 50, 50), picture1);
 }
 }

I feel like t$$anonymous$$s would work, however it hasn't been tested.

 using UnityEngine;
 using System.Collections;
 
 public class Swap : MonoBehavior
 {
     public GameObject[] objects;
     private int currentObject = 0;
     private Random random = new Random();
     
     private void Start()
     {
         for(GameObject i in objects)
         {
             Instantiate(i, new Vector(0,0,0), i.transform.rotation);
             i.SetActive(false);
         }
     }
     
     private void Update()
     {
         if(Input.GetKeyDown(KeyCode.E))
         {
             currentObject = random.Next(0, objects.Length - 1);
             objects[currentObject].SetActive(true);
         }
     }
 }