Database Engine in PHP

Let's now make a website engine where the content of the pages will be stored not in files, but in a database. Suppose we have the following table in the database:

pages
id	title	content
1	title1	<div> content1 </div>
2	title2	<div> content2 </div>
3	title3	<div> content3 </div>

Suppose we want to get our pages by URLs like /page/1, where the number will represent the id of the page we want to get.

Let's start the implementation. First, in a separate file, we will make a connection to the database and connect this file to ours:

<?php
	$link = require 'connect.php';
?>

Get the requested URL:

<?php
	$url = $_SERVER['REQUEST_URI'];
?>

Using a regular expression, split the URL into parts:

<?php
	preg_match('#/page/(\d+)#', $url, $match);
?>

Write the id from the capture group into a variable:

<?php
	$id = $match[1];
?>

Execute a query to the database, getting the requested page by id:

<?php
	$query = "SELECT * FROM pages WHERE id=$id";
	$res = mysqli_query($link, $query) or die(mysqli_error($link));
	$page = mysqli_fetch_assoc($res);
?>

Get the template file:

<?php
	$layout = file_get_contents('layout.php');
?>

In the template file, perform the insertion of the title and content:

<?php
	$layout = str_replace('{{ title }}', $page['title'], $layout);
	$layout = str_replace('{{ content }}', $page['content'], $layout);
?>

Send the assembled website page to the browser:

<?php
	echo $layout;
?>

Let's put it all together and get the following code:

<?php
	require 'connect.php';
	
	$url = $_SERVER['REQUEST_URI'];
	preg_match('#/page/(\d+)#', $url, $match);
	$id = $match[1];
	
	$query  = "SELECT * FROM pages WHERE id=$id";
	$res = mysqli_query($link, $query) or die(mysqli_error($link));
	$page   = mysqli_fetch_assoc($res);
	
	$layout = file_get_contents('layout.php');
	$layout = str_replace('{{ title }}', $page['title'], $layout);
	$layout = str_replace('{{ content }}', $page['content'], $layout);
	
	echo $layout;
?>

Implement the described engine. Test its operation.