I remember in one of the versions of unity there was a FPS tutorial or example. I can’t seem to find it. It was based on a space station sort of location and you fought against robotic drones if I remember correctly.
That no longer exists in these versions but you can find a first person asset in Assets/Import Package/Characters
or search for that on the Assets store in Unity As the publisher and its titled Angry Bots (Unity 4.x only)