Does Anyone Have a Halo-Like Scripts?

You likely aren't going to find anything "spitting-image" of Halo because it's copyrighted by Bungee as well as Microsoft.

@rutter has the best solution, if you want to do a fan remake of Halo, you'll want to look up FPS tutorials, and create the art assets and scripts yourself.

Unity is like Lego, you get the very basic building blocks, but as far as working parts go you have to make those.