Флажок HTML PHP

Я только что добавил флажок в свою контактную форму, чтобы указать, хочет ли пользователь подписаться на мою рассылку новостей или нет. Я бы хотел, чтобы мой PHP-скрипт выводил значение флажка, когда он отправляет мне электронное письмо. Я тщательно искал в Интернете и не могу найти никаких решений, просто люди с похожими проблемами. https://joebaileyphotography.com/contact%20me.html

HTML:

<form method = "post" name = "myemailform" action = "form-to-email.php">

<label class = "label" for = "fname">First Name</label>
<br>
<input type = "text" id = "fname" name = "fname" placeholder = "Your name..">
<br>
<label class = "label" for = "lname">Last Name</label>
<br>
<input type = "text" id = "lname" name = "lname" placeholder = "Your last name..">
<br>
<label class = "label" for = "Email">Email Address</label>
<br>
<input type = "text" id = "Email" name = "Email" placeholder = "Your email address...">
<br>
<label class = "label" for = "subject">Subject</label>
<br>
<textarea id = "subject" name = "subject" placeholder = "Drop me a line..." style = "height:200px"></textarea>
<br>
<input type = "checkbox" id = "subscribeNews" name = "subscribe" value = "newsletter" checked>
<label for = "subscribeNews">Yes, I would like to recieve news from Joe Bailey Photography.</label>
<br>
<br>
<input type = "checkbox" id = "privacyPolicy" name = "privacy" value = "privacy">
<label for = "privacyPolicy">I consent to having this website store my submitted information so they can respond to my inquiry. For more info, read the <a href = "/privacy-policy.html">Privacy Policy.</a></label>
<br>
<br>
<div class = "g-recaptcha" data-sitekey = "6LeqeRkTAAAAAFGmVFmAorEU9n0yL4NDEpSUnM0R"></div>
<br>
<input type = "submit" value = "Send Form">

PHP:

<?php
$response = $_POST["g-recaptcha-response"];
$url = 'https://www.google.com/recaptcha/api/siteverify';
$data = array(
    'secret' => '6LeqeRkTAAAAABjyRvL0c1vrqG3ZmV51O0-S3xcz',
    'response' => $_POST["g-recaptcha-response"]
);
$options = array(
    'http' => array (
        'method' => 'POST',
        'content' => http_build_query($data)
    )
);
$context  = stream_context_create($options);
$verify = file_get_contents($url, false, $context);
$captcha_success=json_decode($verify);
if ($captcha_success->success==false) {
    echo "<p>Please go back and verify you are human.</p>";
} else if ($captcha_success->success==true) {

    $fname = $_POST['fname'];
    $lname = $_POST['lname'];
    $visitor_email = $_POST['Email'];
    $subject = $_POST['subject'];

    $email_subject = "Joe Bailey Photography Contact Form";
    $email_body = "You have received a new message from $fname $lname.\n".
    "Here is the message:\n$subject
    ";

    $to = "[email protected]";
    $headers = "From: $visitor_email \r\n";
    mail($to,$email_subject,$email_body,$headers);
    //done. redirect to thank-you page.
    header('Location: Contact%20Me%20Thank%20You.html#thankyou');
    function IsInjected($str)
    {
    $injections = array('(\n+)',
          '(\r+)',
          '(\t+)',
          '(%0A+)',
          '(%0D+)',
          '(%08+)',
          '(%09+)'
          );
    $inject = join('|', $injections);
    $inject = "/$inject/i";
    if (preg_match($inject,$str))
    {
        return true;
    }
        else
    {
        return false;
    }
    }
}