Can’t this project automatically generated by express be able to achieve such a function? !

There are a few sentences in the automatically generated project app.js

var routes = require('./routes/index');
 ..........
app.use('/', routes);

The content of ./routes/index.js is similar to

var express = require('express');
var router = express.Router();

router.get('/', function(req, res, next) {
  //这里就是生成你默认页面的代码
  //下面这句的意思是用一个叫做index的模板生成页面
  res.render('index', { title: 'Chat' });
});

module.exports = router;