Create a new page in folder /Sources, like example.php with this content:

$template->display('example.tpl');

If you want that this page can be visited by registered users only, then you can use this content:

if(!$user->isOnline()){
    redirect('?view=login');
}
$template->display('example.tpl');

Create a new template file in /templates/ModernBlue like you call in example.php, example.tpl

In your template file you can use any HTML editor.