how could it be possible to add debounce to this script?

now first of all, i don't really want to send the whole script because it's long and really unnecessary to know, i will attatch the start and the end of the script since the rest isn't really needed. (or so i think)

code samples:

start- (lines 14 to 19)

function onChatted(msg, recipient, speaker) 

local source = string.lower(speaker.Name)
msg = string.lower(msg) 

if (msg == "start") then

end- (lines 127 to 134)

end
end

function onPlayerEntered(newPlayer) 
newPlayer.Chatted:connect(function(msg, recipient) onChatted(msg, recipient, newPlayer) end) 
end 

game.Players.ChildAdded:connect(onPlayerEntered)

if anyone here could help me out with this (since i'm still relatively new to scripting), i would be overjoyed, thank you!

(edit:) someone asked for the whole thing, so here it is (please no comments about this being inefficient all i want is for it to work

light1 = script.Parent.Light1
light2 = script.Parent.Light2
light3 = script.Parent.Light3
light4 = script.Parent.Light4
light5 = script.Parent.Light5
light6 = script.Parent.Light6
light7 = script.Parent.Light7
light8 = script.Parent.Light8
light9 = script.Parent.Light9
light10 = script.Parent.Light10
sign1 = script.Parent.sign.text.SurfaceGui.TextLabel
local descendants = script.Parent.barriers:GetDescendants()

function onChatted(msg, recipient, speaker) 

local source = string.lower(speaker.Name)
msg = string.lower(msg) 

if (msg == "start") then
	
script.Parent.sign.Part.RaceStart:play()--makes the start sound play (this is where the actual script starts)
sign1.Text = "everybody get ready! (5)"
wait(1)
sign1.Text = "everybody get ready! (4)"
wait(1)
sign1.Text = "everybody get ready! (3)"
wait(1)
sign1.Text = "everybody get ready! (2)"
wait(1)
sign1.Text = "everybody get ready! (1)"
wait(1)
sign1.Text = "everybody get ready! (0)"
wait(1)
sign1.Text = "lights prepared."
wait(2)

--------------------------------------------------------------------
-- Loop through all of the descendants of the Workspace. If a
-- BasePart is found, the code changes that parts color to green
for index, descendant in pairs(descendants) do
	if descendant:IsA("BasePart") then
		descendant.CanCollide = true
	end
end
--------------------------------------------------------------------
wait(1)

script.Parent.sign.Part.Sound2:play()--makes the start sound play
light1.Transparency = 0
sign1.Text = "5"
wait(1)
light2.Transparency = 0
sign1.Text = "4"
wait(1)
script.Parent.sign.Part.Sound2:stop()--makes the start sound stop
script.Parent.sign.Part.Sound:play()--makes the start sound play
light3.Transparency = 0
sign1.Text = "3"
wait(1)
light4.Transparency = 0
sign1.Text = "2"
wait(1)
light5.Transparency = 0
sign1.Text = "1"
wait(1)
light1.BrickColor = BrickColor.new("Lime green")
light2.BrickColor = BrickColor.new("Lime green")
light3.BrickColor = BrickColor.new("Lime green")
light4.BrickColor = BrickColor.new("Lime green")
light5.BrickColor = BrickColor.new("Lime green")
sign1.Text = "GO!"
--------
-- Loop through all of the descendants of the Workspace. If a
-- BasePart is found, the code changes that parts color to green
for index, descendant in pairs(descendants) do
	if descendant:IsA("BasePart") then
		descendant.CanCollide = false
	end
end
--------
wait(5)
light1.BrickColor = BrickColor.new("Really red")
light2.BrickColor = BrickColor.new("Really red")
light3.BrickColor = BrickColor.new("Really red")
light4.BrickColor = BrickColor.new("Really red")
light5.BrickColor = BrickColor.new("Really red")
sign1.Text = "restarting..." -- do a funky lights sequence because it looks cool
light1.Transparency = 0
light2.Transparency = 1
light3.Transparency = 1
light4.Transparency = 1
light5.Transparency = 0
wait(.5)
light1.Transparency = 1
light2.Transparency = 0
light3.Transparency = 1
light4.Transparency = 0
light5.Transparency = 1
wait(.5)
light1.Transparency = 1
light2.Transparency = 1
light3.Transparency = 0
light4.Transparency = 1
light5.Transparency = 1
wait(.5)
light1.Transparency = 1
light2.Transparency = 0
light3.Transparency = 1
light4.Transparency = 0
light5.Transparency = 1
wait(.5)
light1.Transparency = 0
light2.Transparency = 1
light3.Transparency = 1
light4.Transparency = 1
light5.Transparency = 0
wait(.5)
light1.Transparency = 1
light2.Transparency = 1
light3.Transparency = 1
light4.Transparency = 1
light5.Transparency = 1
sign1.Text = "restart successful!" -- tell the player that the game isnt dead
wait(2)
sign1.Text = "sample text" -- reset the text to the funny sample text

end
end

function onPlayerEntered(newPlayer) 
newPlayer.Chatted:connect(function(msg, recipient) onChatted(msg, recipient, newPlayer) end) 
end 

game.Players.ChildAdded:connect(onPlayerEntered)