Running the "First Electron App" wont show versions?

If you activate the Developer Tools, you should see error messages in the Console like such:

Uncaught ReferenceError: process is not defined
    at index.html:11

You need to activate nodeIntegration and deactivate contextIsolation of the BrowserWindow, so that the process running in the BrowserWindow ("renderer process") is allowed to access Node's process object.

mainWindow = new BrowserWindow({
    width: 800,
    height: 600,
    webPreferences: {
        nodeIntegration: true,
        contextIsolation: false
    }
})

(Before Electron 12, only the nodeIntegration key was needed, and the default value of contextIsolation was false.)

This is your file with correction

const {app, BrowserWindow} = require('electron')
const path = require('path')
let mainWindow
function createWindow () {
    mainWindow = new BrowserWindow({
        width: 800,
        height: 600,
        webPreferences: {
            // I think you don't need this line
            // preload: path.join(__dirname, 'preload.js') 
            nodeIntegration: true
        }
    })
    mainWindow.loadFile('index.html')
    mainWindow.on('closed', function () {
        mainWindow = null
    })
}
app.on('ready', createWindow)
app.on('window-all-closed', function () {
    if (process.platform !== 'darwin') app.quit()
})
app.on('activate', function () {
    if (mainWindow === null) createWindow()
})