How do i add a debug to a touch part?

Ok, so the problem with your script is that there is no Wait() in there, Wait() is basically waiting for the inserted number of seconds, after that, the script will continue. In your case, you just need to add a Wait() and it will be all good.

(I think most people call it "Debounce" instead of "Debug" this is because "Debug" is a whole diffrent thing.)

More info on Wait(): https://developer.roblox.com/en-us/articles/keeping-time

Modified Script:

local Debug = false

script.Parent.Touched:Connect(function(hit)
    local player = hit.Parent:FindFirstChild("Humanoid")
    if player and Debug == false then 
        Debug = true
        local Char = game.Players:GetPlayerFromCharacter(hit.Parent)
        Char.leaderstats.Cash.Value = Char.leaderstats.Cash.Value + 5
        wait(1) -- you can insert the amount of seconds you want to wait within the brackets.
        Debug = false
    end
end)

Hope this helps :)