How do you lower the players camera when pressing a key?

I am trying to make a crouch script for a fps. The camera is supposed to move down and up depending if they are crouching or not.

mouse.KeyDown:Connect(function(key)
    if key == "c" and crouching == 1 then
    crouching = 2
    h.WalkSpeed = h.WalkSpeed - 15
    h.JumpPower = h.JumpPower - 60
    playAnim:Play()
    cam.CFrame = cam.CFrame - Vector3.new(0,5,0)
    script.Parent.CrouchNonfication.Text = "Crouching"
    crouching = 3
    elseif key == "c" and crouching == 3 then
    crouching = 2
    h.WalkSpeed = h.WalkSpeed + 15
    if p.Perk.Value == "Kangaroo" then
    h.JumpPower = 60
    else
    h.JumpPower = 40
    end
    cam.CFrame = cam.CFrame + Vector3.new(0,5,0)
    playAnim:Stop()
    script.Parent.CrouchNonfication.Text = ""
    crouching = 1
    end
end)
end