To get this project on unity you must first set up unity. Refer to this page: http://www.studica.com/blog/how-to-setup-github-with-unity-step-by-step-instructions Then pull the project into an empty folder. After it is done pulling open up unity and open the project. If unity is set up correctly the project will work (you will get errors if not)
Controls are: WASD to move, Arrow Keys to look, and Space to fire. You can also use an xbox controller which is left and right stick for movement and right trigger to fire.