Hey Seif,
Please follow this code:
$data = array('DesiredCareType' => $_SESSION['caretypes']);
$ch = curl_init();
$url = 'http://xxxx.xx/xxx.php';
curl_setopt($ch, CURLOPT_URL, $url);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
curl_setopt($ch, CURLOPT_FOLLOWLOCATION, true);
curl_setopt($ch, CURLOPT_HTTPHEADER, $header);
curl_setopt($ch, CURLOPT_POSTFIELDS, $data);
$output = curl_exec($ch);
curl_close($ch);
echo "<pre>";
print_r($output);