How do I make this detect if a part doesn't contain humanoid?

I am aware that this is a VERY inefficient script, but that's not why its here

local tool = script.Parent local player = game:GetService("Players").LocalPlayer local X = 0 local Debounce = false local Damage = 0 local Ammount = 0 local Conflict = false tool.Equipped:connect(function(mouse) print("Tool equipped!")

mouse.Button1Down:connect(function()
	print("Mouse pressed!")
	if Debounce == true then
		return
	end
	Debounce = true
	local ray = Ray.new(tool.Handle.CFrame.p, (mouse.Hit.p - tool.Handle.CFrame.p).unit * 300)
	local part, position = workspace:FindPartOnRay(ray, player.Character, false, true)
	
	local Charge = Instance.new("Part", workspace)
	Charge.BrickColor = BrickColor.new("Toothpaste")
	Charge.Anchored = true
	Charge.Material = "Neon"
	Charge.Transparency = 0.5
	Charge.Locked = true
	Charge.CanCollide = false
	Charge.FormFactor = "Custom"
	Charge.CFrame = tool.Handle.CFrame
	Charge.Size = Vector3.new(1,1,1)
	local Mesh = Instance.new("SpecialMesh", workspace)
	Mesh.Parent = Charge
	Mesh.MeshType = "Sphere"
	Damage = math.random(10,20)
	Ammount = math.random(1,5)
	Mesh.Scale = Vector3.new(X,X,X)  -Repeats 40 times
	X = X + 0.2
	wait()


	local beam = Instance.new("Part", workspace)
	beam.BrickColor = BrickColor.new("Toothpaste")
	beam.FormFactor = "Custom"
	beam.Material = "Neon"
	beam.Transparency = 0.25
	beam.Anchored = true
	beam.Locked = true
	beam.CanCollide = false
	
	local distance = (tool.Handle.CFrame.p - position).magnitude
	beam.Size = Vector3.new(0.5, 0.5, distance)
	beam.CFrame = CFrame.new(tool.Handle.CFrame.p, position) * CFrame.new(0, 0, -distance / 2)
	if part then															--Problem area
		local humanoid = part.Parent:FindFirstChild("Humanoid")

		if not humanoid then
			humanoid = part.Parent.Parent:FindFirstChild("Humanoid")
			Ammount = 0
			Conflict = false
		end

		if humanoid then
			Conflict = true
		end
	else
		Ammount = 0
		Conflict = false
	end
	local humanoid = part.Parent:FindFirstChild("Humanoid")
	beam.Size = Vector3.new(3, 3, distance)
	while Conflict == true and Ammount > 0 do
		wait(0.1)
		humanoid:TakeDamage(Damage)
		Ammount = Ammount - 1
	end
	wait(Ammount+1)
	Conflict = false
	beam.Size = Vector3.new(2.5, 2.5, distance)
	beam.Transparency = 0.375
	Charge.Transparency = 0.375
	wait()
	beam.Size = Vector3.new(2, 2, distance)
	beam.Transparency = 0.5
	Charge.Transparency = 0.5
	wait()
	beam.Size = Vector3.new(1.5, 1.5, distance)
	beam.Transparency = 0.675
	Charge.Transparency = 0.675
	wait()
	beam.Size = Vector3.new(1, 1, distance)
	beam.Transparency = 0.75
	Charge.Transparency = 0.75
	wait()
	beam:Destroy()
	Charge:Destroy()
	X = 0
	wait(5)
	Debounce = false
end)																	--Problem Area End

end)

In short. The laser works if it hits a part containing Humanoid, but it doesn't work if it hits nothing or a part doesn't contain Humanoid