Mail

<?php
if(isset($_POST['submit'])){
    $to = "zaloha15@gmail.com"; // this is your Email address
    $from = $_POST['email']; // this is the sender's Email address
    $first_name = $_POST['first_name'];
    $last_name = $_POST['last_name'];
    $subject = $_POST['item'];
    $subject2 = "Copy of your form submission";
    $message = $first_name . " " . $last_name . " Vám napsal:" . "\n\n" . $_POST['message'];
    $message2 = "Zde je kopie Vaší zprávy: " . $first_name . "\n\n" . $_POST['message'];

    $headers = "From:" . $from;
    $headers2 = "From:" . $to;
    $sent = mail($to,$subject,$message,$headers);
    $sent2 = mail($from,$subject2,$message2,$headers2); // sends a copy of the message to the sender
    if($sent)
    {
    echo "Email se úspěšně odeslal. Děkujeme " . $first_name;}
    else
    {
    echo "Email se neuspělo odeslat " . $first_name;}
    // You can also use header('Location: thank_you.php'); to redirect to another page.
    }
?>

<!DOCTYPE html>
<head>
<title>Email</title>
<meta charset="UTF-8">
</head>
<body>

<form action="" method="post">
Vaše jméno: <input type="text" name="first_name"><br>
Vaše příjmení: <input type="text" name="last_name"><br>
Váš email: <input type="text" name="email"><br>
Předmět: <input type="text" name="item"><br>
Zpráva:<br><textarea rows="5" name="message" cols="30"></textarea><br>
<input type="submit" name="submit" value="Odeslat">
</form>

</body>
</html>