If you want your game to never be “cracked” or for anyone to be able to see your asset files, then you need to move your entire game to a server, and only give a simple “viewer” application to your players, which will do nothing but show a video stream from your server that is actually running the game.
It’s basically impossible to protect your assets completely. You can make it harder, but it’ll never be impossible.
You can use GDMaim to make it more difficult to read and understand your GDScript code:
And you can use pck encryption to make it very slightly more difficult to get your assets, but if someone wants to get them, they will.
I’d recommend just making a fun game and not worry about any of this too much. Do the bare minimum that requires barely any effort on your part, and be done with it.