Enable or disable a gameobject with a buttonpress

Hi I want to make a script that enables o disables an object pressing a key, this is my script but it does anything

 using UnityEngine;
 using System.Collections;
 
 public class changetool : MonoBehaviour {
     
     // Update is called once per frame
  void Update () 
     {
       if(Input.GetButtonDown("o"))
         {
         GameObject.FindWithTag("Pick").SetActive(true);   //this is a pickaxe
         GameObject.FindWithTag("Arma").SetActive(false);  //this is a weapon
         }
     }    
 }