How to fix end of finish error in my script in lua in roblox studio in my local script at line 16?

The exception that was raised was an EOF or End of File. It is usually cause by an open parenthesis missing it's partner, and the compiler reached the end of the Script trying to look for it. This of which is your case; your Connect method's argumental parentheses weren't closed, therefore your code is reading:

Mouse.Button1Down:Connect(

To solve this issue, make sure to enclose the parentheses next time.

local Player = game:GetService("Players").LocalPlayer
local Mouse = Player:GetMouse()

local Character = Player.Character or Player.CharacterAdded:Wait()
local Humanoid = Character:WaitForChild("Humanoid")

local PlayerGui = Player:WaitForChild("PlayerGui")
local WoodChopper = PlayerGui:WaitForChild("WoodChopper")
local ChopperBackground = WoodChopper:WaitForChild("BG")
local ChopperBar = ChopperBackground:WaitForChild("Bar")
local ChopProgress = ChopperBar:WaitForChild("Progress")

local CanGetLeaves = true

local function ShowProgress(Leaves)
	if (Leaves == "Leaves") then
		local Direction = Enum.EasingDirection.Out
		local Style = Enum.EasingStyle.Linear
		ChopProgress:TweenSize(UDim2.new(1,0,1,0), Direction, Style, 1, true)
	end
end

Mouse.Button1Down:Connect(function()
	local Wood = Mouse.Target
	if (Wood and Wood.Parent.Name == "Leaves" and CanGetLeaves) then
		if (Player:DistanceFromCharacter(Wood.Position) < 10) then
			ChopperBackground.Visible = true
			Humanoid.WalkSpeed = 0
			ShowProgress("Leaves")
			Humanoid.WalkSpeed = 16
			for _,Leaf in pairs(Wood.Parent.Leaves:GetChildren()) do
				if Leaf:IsA("Leaves") then
					Leaf.Anchored = false
				end
			end
		end
		Wood:Destroy()
   		BG.Visible = false
		CanGetLeaves = true
	end
 end)

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