How to switch in realistic First Person ?

As zeOrb pointed out … that will give you your basic FPS view which includes the Player Controller, Player Object, and Game Mode.

Failing that you would have to create it all yourself … you could look at various other FPS examples out there to see how it is done. This includes having to set up your player, set up your control inputs and all the other stuff that the FPS template does for you.

My suggestion is use the FPS Template as indicated by zeOrb. Good luck. 8-}