What part in the player's character is used for camera manipulation? ex: Head's CFrame = view in first person

Is the Head the part that is being used in all characters to show the first-person view?

Try Reading this post:

it answers your question, from what i think its the HumanoidRootPart. I mean yea you could make the camera follow the head but from original the camera follows the HumanoidRootPart