I think I should also ask if there is to make the whole album go into full screen mode including the index page? Perhaps it just isn't a thing
The only thing a skin can do is offer a "fullscreen" button on the index page, like the one on the right side, here:
https://jefftucker.jalbum.net/skins/neptune/dark/
A page can't automatically open itself in fullscreen mode. In fact, even within an album, if you open a folder, the browser will drop out of fullscreen mode, because as far as the browser is concerned, it's a new page - it doesn't know that it's part of the same "show."
It's a browser security thing. If a page could open in fullscreen, it could fool you into thinking you were on some other site, and steal logins and passwords.