Can't get Serving Static Files using node js (express)

I have learning Node JS and try to open the Serving Static Files using the below function on node js express. But I got the Cannot GET error check the screenshot

I have a proper folder structure.

I refer to the below article
https://www.tutorialspoint.com/nodejs/nodejs_express_framework.htm

app.use(express.static('public'));

Here is the full code

var express = require('express');
var app = express();

app.use(express.static('public'));

app.get('/', function (req, res) {
   res.send('Hello World');
})

var server = app.listen(8081, function () {
   var host = server.address().address
   var port = server.address().port

   console.log(host, port)
})

Folder structure

node_modules
server.js
public/
public/images
public/images/Minions_characters.png

>Solution :

app.use(express.static('public'));

You didn’t specify a path as the first argument to use.

You’ve mounted the contents of the public directory at /

Therefore the correct URL does not start with /public

Either:

• remove /public from the URL
• add /public to the mount point: app.use('/public/, express.static('public'));