How can i change registration email send to admin
Unlike normal users there's is no UI to change the text of the message sent to administrator on account creation.

You could implement hook_mail_alter(), to achieve this via a custom module:

function MODULE_mail_alter(&amp;$message) {
  if ($message['id'] == 'user_register_pending_approval_admin') {
    //$message['body'] is the array you want to change.
    $message['body'][] = 'Your custom message for admin goes here.....';
  }
}