How can I fix my else section in my function? [Answered]

This seems to be a matter of logic. The first thing I noticed was that if line 11 does not pass, line 18 will not pass either. This is because both are checking for Debounce == false. This leads me to think that you may want to put an end before line 17, and remove one of the ends that you have at the end of your code.

Again, more information would be very helpful.

Something like this...

sp = script.Parent
Debounce = false


sp.Touched:connect(function(hit)
    local player = game.Players:GetPlayerFromCharacter(hit.Parent)
    local Human = hit.Parent:FindFirstChild("Humanoid")
    if Human ~= nil then
        print("Human is true")
        if player.Backpack:FindFirstChild("Sword") == nil then
            if Debounce == false then Debounce = true
                print("Player does not have tool!")
                local Tool = game.ReplicatedStorage:FindFirstChild("Sword")
                Tool = Tool:Clone()
                Tool.Parent = player.Backpack
                Debounce = false
            end
         else
            if Debounce == false then Debounce  = true
                print("Player does have tool!")
                local msg = Instance.new("Message", player.PlayerGui)
                msg.Text = "You cannot get this tool twice!"
                wait(2)
                Debounce = false
                msg:remove()
            end
        end
    end
end)

P.S. Consider tidying up your code and logic! It will help you in the long run for debugging cases like these.