I cant find any tutorials on it so it would be great if someone could tell me what it does.
CFrame.fromEulerAnglesXYZ
CFrame.fromEulerAnglesXYZ is a constructor for CFrame. It's used to manipulate the rotation of an object. It takes in 3 parameters(X,Y,Z) and each of them are required to be in radians. You can easily convert degrees to radians by using math.rad(). It's also the same as CFrame.fromAngles.