hall@home-pc:/tmp$ cat dani.php
<!-- dani.php -->
<form method="post" action="dani.php">
    <textarea name="urls"></textarea>
    <button type="submit">Processar</submit>
</form>
<?php
if (!isset($_POST['urls'])) {
    exit;
}

$urls = explode(PHP_EOL, $_POST['urls']);
foreach ($urls as $url) {
    echo $url, PHP_EOL;
}
?>