Unity networking create & join with custom character?,

Im new to unity, sorry if this is a bad question.

What I want to happen: User selects what parts they want and pressed build. They then join server. Other users can see their player model, and likewise, the player can see other users character models.

 Selection Script 
 
 using System.Collections.Generic;
 using UnityEngine;
 using UnityEngine.UI;
 
 public class controller : MonoBehaviour
 {
     string prevh;
     string prevl;
     public GameObject legs;
     private List<GameObject> headModels;
     public GameObject heads;
     public GameObject NewParent;
     private List<GameObject> legModels;
     Dictionary<string, int> LegDict = new Dictionary<string, int>();
     Dictionary<string, int> HeadDict = new Dictionary<string, int>();
 
 
 
 
     [SerializeField] Dropdown DropLegs;
     [SerializeField] Dropdown DropHeads;
     private void Start()
     {
         //Generate list of body parts and hide them
         legModels = new List<GameObject>();
         int x = 0;
         foreach (Transform t in legs.transform)
         {
             //Legs
             legModels.Add(t.gameObject);
             t.gameObject.SetActive(false);
             LegDict.Add(t.ToString(), x);
             x++;
             DropLegs.options.Add(new Dropdown.OptionData(t.ToString()));
         }
         //Heads
         x = 0;
         headModels = new List<GameObject>();
         foreach (Transform t in heads.transform)
         {
             t.gameObject.SetActive(false);
             headModels.Add(t.gameObject);
             HeadDict.Add(t.ToString(), x);
             x++;
             DropHeads.options.Add(new Dropdown.OptionData(t.ToString()));
 
         }
 
     }
 
     private void Update()
     {
         //Shows built parts infront of camera
 
         //Display Head
         int menuIndex = DropHeads.GetComponent<Dropdown>().value;
         List<Dropdown.OptionData> menuOptions = DropHeads.GetComponent<Dropdown>().options;
         string valueh = menuOptions[menuIndex].text;
         //Prevents from constantly updating
         if (valueh != prevh)
         {
             //Clears other models
             if (HeadDict.ContainsKey(valueh))
             {
 
                 //Hides other models
                 foreach (Transform t in heads.transform)
                 {
                     t.gameObject.SetActive(false);
                 }
                 //Displays the current model
                 headModels[HeadDict[valueh]].SetActive(true);
             }
         }
         prevh = valueh;
 
         //Repeat of the code for heads but with legs
         //Display legs
         menuIndex = DropLegs.GetComponent<Dropdown>().value;
         menuOptions = DropLegs.GetComponent<Dropdown>().options;
         string valuel = menuOptions[menuIndex].text;
         if (valuel != prevl)
         {
             if (LegDict.ContainsKey(valuel))
             {
                 foreach (Transform t in legs.transform)
                 {
                     t.gameObject.SetActive(false);
                 }
                 legModels[LegDict[valuel]].SetActive(true);
             }
         }
         prevl = valuel;
 
     }
 
     //Called when the build button is pressed.
     public void Build()
     {
         //Save The Chosen Parts to a GameObject
         GameObject myLeg = Instantiate(legs) as GameObject;
         myLeg.transform.parent = NewParent.transform;
         myLeg.transform.position = NewParent.transform.position;
         GameObject myHead = Instantiate(heads) as GameObject;
         myHead.transform.parent = NewParent.transform;
         myHead.transform.position = NewParent.transform.position;
         Debug.Log("Built Mech with head: " + prevh + " and legs: " + prevl);
     }
 
 }
 
 
 
 
 
 
 Network Script
 
 using UnityEngine;
 using UnityEngine.Networking;
 using UnityEngine.Networking.NetworkSystem;
 using UnityEngine.UI;
 
 public class MyNetManager : NetworkManager {
 
     public GameObject PlayerPrefab;
     public GameObject UI;
 
 
     public void StartupHost()
     {
         SetPort();
         NetworkManager.singleton.StartHost();
         HideUI();
     }
 
     public void HideUI()
     {
         UI.SetActive(false);
     }
     public void JoinGame()
     {
         SetIPAddress();
         SetPort();
         NetworkManager.singleton.StartClient();
         HideUI();
     }
 
     void SetIPAddress()
     {
         string ipaddress = GameObject.Find("InputFieldIPAddress").transform.Find("Text").GetComponent<Text>().text;
         NetworkManager.singleton.networkAddress = ipaddress;
     }
 
     void SetPort()
     {
         NetworkManager.singleton.networkPort = 7777;
     }
 
     private void LevelWasLoaded(int level)
     {
         if (level == 0)
         {
             Debug.Log("Loaded First");
             SetupMenuSceneButtons();
         }
         else
         {
             Debug.Log("Loaded 2nd");
             SetupOtherSceneButtons();
         }
     }
 
     void SetupMenuSceneButtons()
     {
         GameObject.Find("ButtonStartHost").GetComponent<Button>().onClick.RemoveAllListeners();
         GameObject.Find("ButtonStartHost").GetComponent<Button>().onClick.AddListener(StartupHost);
 
         GameObject.Find("ButtonJoinGame").GetComponent<Button>().onClick.RemoveAllListeners();
         GameObject.Find("ButtonJoinGame").GetComponent<Button>().onClick.AddListener(JoinGame);
     }
 
     void SetupOtherSceneButtons()
     {
         GameObject.Find("ButtonDisconnect").GetComponent<Button>().onClick.RemoveAllListeners();
         GameObject.Find("ButtonDisconnect").GetComponent<Button>().onClick.AddListener(NetworkManager.singleton.StopHost);
     }
 
     public override void OnServerAddPlayer(NetworkConnection conn, short playerControllerId, NetworkReader extraMessageReader)
     {
         int id = 0;
         if (extraMessageReader != null)
         {
             IntegerMessage i = extraMessageReader.ReadMessage<IntegerMessage>();
             id = i.value;
         }
         GameObject playerPrefab = PlayerPrefab;
         GameObject player;
         Transform startPos = GetStartPosition();
         if (startPos != null)
         {
             player = (GameObject)Instantiate(playerPrefab, startPos.position, startPos.rotation);
         }
         else
         {
             player = (GameObject)Instantiate(playerPrefab, Vector3.zero, Quaternion.identity);
         }
         NetworkServer.AddPlayerForConnection(conn, player, playerControllerId);
     }
 
 }

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