How do I lock first person mode?

I want to make a first person shooter game but I don't know how to lock the camera to first person mode

Check out this: http://wiki.roblox.com/index.php?title=API:Class/Player/CameraMode

You can lock it to first person by having this into your script.

game:GetService('Players').LocalPlayer.CameraMode = Enum.CameraMode.LockFirstPerson

What you also can do is...

That you go into StarterPlayer, Open the Properties window. And change the cameramaxzoomdistance to 0.5

I personally use this when i create FPS games