How and why cash GUI script is not working and cant spot the error please help me, please?

I think it is like this:

while true do
    Wait(0.1)
    script.Parent.Text == game.Players.LocalPlayer:WaitForChild("leaderstats"   ):WaitForChild("stat name")
end

Here is a little more complex version.

local Plr = game.Players.LocalPlayer --The Player
local Stats = Plr.leaderstats --The leaderstats
while Stats ~= nil do -- While Stats Is in the game
wait()
script.Parent.Text = "Cash: "..Stats.Cash.Value.."$"
end