How to make the script work only once per player when he runs the script?

I tried to make a script that instancing a BoolValue, and if Value was true, player can't run script on second time. But when i tried to test, it's just wont work. Nothing in Output. Can you help me please?

player = game.Players.PlayerAdded:Connect(function(player)
local function onClick(click) 
	local RS = game:GetService("ReplicatedStorage")
	local QuirkTrue = Instance.new("BoolValue", player.Backpack)
	if QuirkTrue.Value == true then return end
	if not true then
	local quirk = RS.Quirks.Common
	local quirktable = {}
	quirktable[1] = quirk.Explosion
	quirktable[2] = quirk.Electrification
	quirktable[3] = quirk.Engine
	quirktable[4] = quirk.Quirkless
	quirktable[5] = quirk.Regeneration
	for i = 1, 1 do 
	  local localquirk = quirktable[math.random(1,5)]
      local localquirk2 = localquirk:Clone()
	  localquirk2.Parent = player.Backpack 
	  QuirkTrue.Value = true
	end
end
local function test()
	print("oh uh")
end
test()
script.Parent.ClickDetector.MouseClick:connect(onClick)
end
end)

Now before I go ahead and answer this:

1. Where is the "script.Parent.ClickDetector" located? (this should be somewhere under Workspace)
2. The main concern I'm seeing just by looking at the code is that the ClickDetector Function is inside the PlayerAdded function, making me think that clicking the Detector won't set off the second function.
3. You've already called the player inside the PlayerAdded so you don't need the "player =" phrase.
4. I tried this out, and found that you can't add a Bool Value to the Backpack unless it was pre-placed inside the "Starter Pack" (the reason for this is the Backpack is meant to carry Tools) so you'll need to add the Bool Value to the Player instead.

With all this in mind, I've adjusted the code like this:

game.Players.PlayerAdded:Connect(function(player)
	local QuirkTrue = Instance.new("BoolValue", player)
	QuirkTrue.Name = "QuirkTrue"
end)

function onClick(click)
	local RS = game:GetService("ReplicatedStorage")
	local QuirkTrue = click.QuirkTrue
	if QuirkTrue.Value == true then return end
	if QuirkTrue.Value ~= true then
		local quirk = RS.Quirks.Common
		local quirktable = {}
		quirktable[1] = quirk.Explosion
		quirktable[2] = quirk.Electrification
		quirktable[3] = quirk.Engine
		quirktable[4] = quirk.Quirkless
		quirktable[5] = quirk.Regeneration
		for i = 1, 1 do
			local localquirk = quirktable[math.random(1,5)]
			local localquirk2 = localquirk:Clone()
			localquirk2.Parent = click
			QuirkTrue.Value = true
		end
	end
end

script.Parent.ClickDetector.MouseClick:connect(onClick)

The first function is the PlayerAdded Function you used, however, it is shortened to only give the Bool Value. The second function is the ClickDetector. Assuming you are using Particles, you would want to replace the following line of code

		localquirk2.Parent = click

with this:

		local char = game.Workspace:FindFirstChild(click.Name)
		local root = char.HumanoidRootPart
		localquirk2.Parent = root

this way, the Particle Emitter would be in the Character, rather than the Player (which is called by "click")