How do I make this Brick not kill me when I click on it?

Pcall is a meathod of handling errors in lua I'm not going to in depth but here is a link to a page explaining it Link

Assuming that "PurpleBrick" is the part you want the user to click and that it is parented by workspace. And that "PurpleBrick" has a Click Detector

local partToClick = game.Workspace.PurpleBrick
local damage = true

local player = game.Players.LocalPlayer

partToClick.ClickDetector.MouseClick:Connect(function()
	damage = false
end)

for i = 0, 3, 1 do
	if damage and i == 3 then
		player.Character.Humanoid:TakeDamage(100)
	end
	wait(1)
end

The above code will give the player 3 seconds to click on the button or face demise.

If you wanted to make it so the player has 3 seconds from the first time they click the button to click the button again, then you would use this code

local partToClick = game.Workspace.PurpleBrick
local damage = true

local player = game.Players.LocalPlayer

local firstClick = true

partToClick.ClickDetector.MouseClick:Connect(function()
	
	if firstClick then
		firstClick = false
		
		for i = 0, 3, 1 do
			if damage and i == 3 then
				player.Character.Humanoid:TakeDamage(100)
			end
			wait(1)
		end
		
	else
		damage = false
	end
	
end)

Feel free to dm me if you have more questions (I might not respond til after school)

Code is tested and working

If this answer helped you please accept it :)