What happens to the request after it is entered into…

Domain Name Resolution: The browser determines the server's IP address using a DNS resolver (browser cache, OS cache, hosts file, DNS servers).
Establishing TCP Connection: The browser establishes a connection with the server using the obtained IP address and port (usually 80 for HTTP, 443 for HTTPS).
Sending HTTP Request: The browser forms and sends an HTTP request (GET, POST, etc.), containing method, URL, headers (e.g., User-Agent, Referer, Cookie), and possibly a request body (e.g., for POST).
Processing Request on Server: The server receives the request, the web server (Apache, Nginx, etc.) determines the handler (e.g., PHP-FPM). The PHP interpreter runs the script.

Executing PHP Script: The PHP script processes the request: connects to the database, performs logic, generates an HTML page or other data.

// Example of executing a PHP script on the server
<?php

// Connecting to the database
$conn = new mysqli("localhost", "user", "password", "dbname");

// Checking the connection
if ($conn->connect_error) {
    die("Connection error: " . $conn->connect_error);
}

// Executing the query
$sql = "SELECT * FROM users WHERE id = 1";
$result = $conn->query($sql);

// Processing results
if ($result->num_rows > 0) {
    while($row = $result->fetch_assoc()) {
        echo "Hello, " . $row["name"];
    }
} else {
    echo "User not found.";
}

// Closing the connection
$conn->close();

?>

Forming HTTP Response: The PHP script and web server form an HTTP response, including status code (e.g., 200 OK, 404 Not Found), headers (Content-Type, Content-Length, etc.), and the response body (usually HTML).
Sending HTTP Response: The server sends the HTTP response back to the browser over the established TCP connection.
Receiving and Processing Response: The browser receives the response, parses headers, determines content type, displays the page to the user, executes scripts (JavaScript), loads additional resources (CSS, images).
Closing TCP Connection: The connection is usually closed after receiving the response unless connection keep-alive mechanisms are used.

What happens to the request after it is entered into the address bar?