How to make and include different routing files inside one route file?

Something like this for modules.

PHP Code:

app/Config/Routes.php 
//.. Other routes

// Add this to Footer 

// Including all module routes

$modules_path = ROOTPATH . 'Modules/';
$modules      = scandir($modules_path);

foreach ($modules as $module)
{
    if ($module === '.' || $module === '..')
    {
        continue;
    }

    if (is_dir($modules_path) . '/' . $module)
    {
        $routes_path = $modules_path . $module . '/Config/Routes.php';
    
        if (file_exists($routes_path))
        {
            require $routes_path; 
        }
        else
        {
            continue;
        }
    }
} 


Should get you going.

Would you please explain this code to me ?
Where should I put this code ?