On the FPS tutorial page:
…three is mention of an FPSCamera class, which doesn’t exist. My guess is that it used to exist but the tutorial was updated at some point and all references to it were not removed.
Secondly, the part where it asks you to move the default position of the camera so that it is near to the character’s eye level doesn’t work. It asks you to put the following code in the FPSCharacter constructor:
FPSCameraComponent->SetRelativeLocation(FVector(0.0f, 0.0f, 50.0f + BaseEyeHeight));
…this did not work for me. I moved it to the BeginPlay() function and it worked as it should, so it seems that the constructor was called too early before some other dependencies were initialised maybe.