$urls = ['url1', 'url2', 'url3', 'url4', 'url5'];
foreach ($urls as $url) {
    $params = [
        'url' => $url
    ];
    $ch = curl_init('https://site.com/islem.php?'.http_build_query($params));
    curl_exec($ch);
    curl_close($ch);
}