How to access a file from storage in Laravel 5.8

I have a file inside my storage folder. Located path :

storage/app/public/$/10012940/gallery/289sdas98e.jpg

$, 10012940 and 289sdas98e.jpg is dynamic and can change.

Route::get('storage/{$folderDirectory1}/{$customerReference}/gallery/{file}', function ($filename)
{

});

Since its a nested folder I cannot find much on internet as to what the route should look like. Also how to go about doing something like that.

I am trying to find a way to access this path via the route so that I can write a middleware to authenticate before making this accessible to the end user.

I am storing the file inside the storage folder due to the visibility. I would like to control who should have access to viewing the image

via Chebli Mohamed