I customized your code and now it displays the amount of Ether from the Account:

const showAccount = document.querySelector('.showAccount');
const showBalance = document.querySelector('.showBalance');

getAccount();
loadBalance();


async function getAccount() {
    const accounts = await ethereum.request({ method: 'eth_requestAccounts' });
    const account = accounts[0];
    showAccount.innerHTML = account;
}

function loadBalance(){
    web3Provider = null;
    contracts = {};
    account = '0x0';
    const Web3 = require("web3");
    const ethEnabled = async () => {
        if (window.ethereum) {
            await window.ethereum.send('eth_requestAccounts');
            window.web3 = new Web3(window.ethereum);
            return true;
        }
    }
    if (typeof web3 !== 'undefined') {
        // If a web3 instance is already provided by Meta Mask.
        web3Provider = web3.currentProvider;
        web3 = new Web3(web3.currentProvider);
    } else {
        // Specify default instance if no web3 instance provided
        web3Provider = new Web3.providers.HttpProvider('http://localhost:7545');
        web3 = new Web3(App.web3Provider);
    }
    $.getJSON("Market.json", function (market) {
        console.log("initializing Market contract")

        // Instantiate a new truffle contract from the artifact
        contracts.Market = TruffleContract(market);
        // Connect provider to interact with contract
        contracts.Market.setProvider(web3Provider);
    });
    $.getJSON("Users.json", function (users) {
        console.log("initializing User contract")
        // Instantiate a new truffle contract from the artifact
        contracts.Users = TruffleContract(users);
        // Connect provider to interact with contract
        contracts.Users.setProvider(App.web3Provider);
    });

    var marketInstance;
    var userInstance;

    var loader = $("#loader");
    var content = $("#content");

    //loader.show();
    content.show();

    // Load account data
    console.log("loading account data")
    var currentAccount;
    web3.eth.getCoinbase(function (err, account) {
        if (err === null) {
            console.log("Your Account: " + account)
            account = account;
            currentAccount = account;
            web3.eth.getBalance(account, function(err, balance) {
                if (err === null) {  //Note:set id="accountBalance" in your html page
                    $("#accountBalance").text(web3.fromWei(balance, "ether") + " ETH");
                }
            });
        }
    });
}