explain this and how can i improve it:
using System;
using System.Collections;
using System.Collections.Generic;
using System.Threading.Tasks;
using UnityEngine;
using UnityEngine.UI;
using Nethereum.Web3;
using Nethereum.Util;
using Nethereum.Hex.HexTypes;
using Nethereum.Contracts;
using Nethereum.ABI.FunctionEncoding.Attributes;
using EasyUI.Toast;
using System.Numerics;
using PlayFab;
using PlayFab.ClientModels;

public class TokenAndBalanceChecker : MonoBehaviour
{
    public Button checkButton; // Unified button for both checks

    public static int extraGrenades = 0; // Track the number of extra grenades the player should have due to high balance
    public static int availableCharacters = 0; // Track the number of characters the player can choose

    // public static int ownedTokenId = -1; // If the user owns a token, its ID will be stored here
    public static List<int> ownedTokenIds = new List<int>();

    // Start is called before the first frame update
    void Start()
    {
        checkButton.onClick.AddListener(() =>
        {
            StartCoroutine(CheckBalance());
            CheckOwnership();
            StoreUserAddress();
        });
    }

    private IEnumerator CheckBalance()
    {
    string account = PlayerPrefs.GetString("Account");

        if (string.IsNullOrEmpty(account))
        {
            Toast.Show("Wallet not connected", 3f, ToastPosition.TopRight);
            yield break;
        }

        // Create a new instance of Web3 with an RPC client
        var web3 = new Web3("https://rpc.exosama.com/");

        // Start the GetBalanceTask and wait for it to complete
        yield return GetBalanceTask(web3, account);
    }

    private IEnumerator GetBalanceTask(Web3 web3, string account)
    {
        var getBalanceRequest = web3.Eth.GetBalance.SendRequestAsync(account);
        yield return new WaitUntil(() => getBalanceRequest.IsCompleted);

        try
        {
            // Convert the balance from NAME_1 to Ether
            var balanceInEther = Web3.Convert.FromWei(getBalanceRequest.Result.Value);

            Debug.Log("Account Balance: " + balanceInEther + " SAMA");
            Toast.Show("Account Balance: " + balanceInEther + " SAMA", 3f, ToastPosition.TopRight);

            // Check balance and assign extra grenades
            if (balanceInEther > 10000)
            {
                extraGrenades = 3;
            }
            else if (balanceInEther > 5000)
            {
                extraGrenades = 2;
            }
            else if (balanceInEther > 1000