The basic template includes the admin toolbar, the menu, and the basic layout to render your page.

<?php
osc_add_hook('admin_page_header','customPageHeader');
    function customPageHeader(){
        echo '<h1>' . __('Custom Layout') . '</h1>';
    }
?>
<?php osc_current_admin_theme_path( 'parts/header.php' ); ?>
    <!-- You content here -->
    <!-- #You content here -->
<?php osc_current_admin_theme_path( 'parts/footer.php' ); ?>