What are the recommended steps for a PHP beginner to create a contact form that sends messages to a specific admin user?

To create a contact form that sends messages to a specific admin user, you will need to set up a form with fields for name, email, message, and possibly a subject. When the form is submitted, the PHP script will need to process the input, validate the data, and then send an email to the admin user with the message content.

<?php
if ($_SERVER["REQUEST_METHOD"] == "POST") {
    $admin_email = "admin@example.com";
    $name = $_POST['name'];
    $email = $_POST['email'];
    $subject = $_POST['subject'];
    $message = $_POST['message'];
    
    // Validate input
    if (!empty($name) && !empty($email) && !empty($message)) {
        $email_message = "Name: $name\n";
        $email_message .= "Email: $email\n";
        $email_message .= "Subject: $subject\n\n";
        $email_message .= "Message:\n$message";
        
        // Send email
        mail($admin_email, "Contact Form Submission", $email_message);
        
        echo "Message sent successfully!";
    } else {
        echo "Please fill in all required fields.";
    }
}
?>

<form method="post" action="<?php echo $_SERVER['PHP_SELF']; ?>">
    <label for="name">Name:</label>
    <input type="text" name="name" required><br>
    
    <label for="email">Email:</label>
    <input type="email" name="email" required><br>
    
    <label for="subject">Subject:</label>
    <input type="text" name="subject"><br>
    
    <label for="message">Message:</label><br>
    <textarea name="message" required></textarea><br>
    
    <input type="submit" value="Submit">
</form>