How to I show hidden games on the new my games and apps layout?

No unfortunately the only way they can be restored to be seen is by going in to your profile and got to the games and apps part and click show all it should restore any of the hidden games and apps

And how do i do that i go into my games and apps and i can't seem to toggle show all games and apps that are hidden from the list

You can toggle the hidden games and apps. Go to your ‘Games & apps’ list and ‘show all’

Thank you for letting me know. I'm not sure why it would be removed from the library itself. Perhaps try going to My Games & Apps then use the filters at the top of the page to show your Hidden items. Perhaps it was hidden accidentally.

If the game isn't hidden, as the above poster mentioned, it's possible that perhaps you've ticked some of the filters within My Games and Apps which is why some of your games aren't showing up. When you're in the My Games and Apps section, and in your Full
Library, scroll over to "Filter" and double check that you're looking at "All Console Types".

It's most likely to be a game you've hidden by accident (or somebody else hid by accident) though.

Sometimes games that you purchase just don't show up in your Ready To Install list, as well. It's a known issue and has happened to lots of people including myself. Every now and then, you will see forum posts on it. If you have a game that is not showing
there, but you know you purchased it, it could just be a bug on Xbox's end. I try to remember the games I've purchased or want to play and if they aren't there, I manually search for them in the Store and install them that way.