Mouse Cursor Not Showing Up

Unity Engine
,
1

Hello, I have an inventory system. I saw this video of this guy who made one himself, but when his inventory shows, he can use the mouse cursor. Is there anyway to do this that I do not know of?

I am new to scripting by the way.

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.UI;

public class Inventory : MonoBehaviour
{
    public GameObject inventory;
    public GameObject slotHolder;
    public GameObject itemHolder;
    private bool inventoryEnabled;

    private int slots;
    private Transform[] slot;

    private GameObject itemPickedUp;
    private bool itemAdded;

    public void Start()
    {
        //Slots being detected
        slots = slotHolder.transform.childCount;
        slot = new Transform[slots];
        DetectInventorySlots();
    }

    public void Update()
    {
       
        if (Input.GetKeyDown(KeyCode.Tab))
        {
            inventoryEnabled = !inventoryEnabled;
        }

        if (inventoryEnabled)
            inventory.SetActive(true);
        else
            inventory.SetActive(false);
    }

    public void OnTriggerEnter(Collider other)
    {
        if(other.tag == "Item")
        {
            print("Colliding!");
            itemPickedUp = other.gameObject;
            AddItem(itemPickedUp);
        }
    }

    public void OnTriggerExit(Collider other)
    {
        if(other.tag == "Item")
        {
            itemAdded = false;
        }
    }

    public void AddItem(GameObject item)
    {
        if (itemPickedUp == null)
            return;

        for (int i = 0; i < slots; i++)
        {
            if (slot[i] != null)
            {
                Slots slots = slot[i].GetComponent<Slots>();

                if ((slots != null) && (slots.empty) && itemAdded == false)
                {
                    slots.item = itemPickedUp;

                    slots.itemIcon = (itemPickedUp.GetComponent<Item>() != null) ? itemPickedUp.GetComponent<Item>().icon : null;

                    item.transform.parent = itemHolder.transform;
                    item.transform.position = itemHolder.transform.position;
                    if (item.GetComponent<MeshRenderer>())
                        item.GetComponent<MeshRenderer>().enabled = false;

                    Destroy(item.GetComponent<Rigidbody>());

                    itemAdded = true;
                }
            }
        }
    }

    public void DetectInventorySlots()
    {
        for (int i = 0; i < slots; i++)
        {
            slot[i] = slotHolder.transform.GetChild(i);
        }
    }
}
2

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