How to cycle weapons and parent it?

I am trying to make a simple weapons cycle for a simple fps I was making for fun. I decided for weapon cycle to try to instantiate the prefab and parent it to where it belongs (Not sure if this is best way to do a weapons cycle if not let me know). However I can't seem to instantiate it correctly. I am also stuck on how I would parent it. Thanks in advance.

 using UnityEngine;
 using System.Collections;
 
 public class WeaponSwitch : MonoBehaviour {
     public GameObject Magnum;
     public GameObject Player;
 
     // Use this for initialization
     void Start () {
     
     }
     
     // Update is called once per frame
     void Update () {
         if (Input.GetKeyDown("1"))
         {
             GameObject obj;
             obj = (GameObject)Instantiate(Magnum, Player.transform.position, Player.transform.rotation);
             
         }
     }
 }