Why is the rest of the code not running? thanks to the three guys that downvoted gave me a shoutout

It's not running code after the while wait() do, loop. How would i stop that, and why? I wan't a clear answer : -)

local Player = game.Players.LocalPlayer
local AmountOfCash

function CheckStats()
	
	if Player then
		local Cash = Player.leaderstats.Cash.Value
		
		return Cash
	end
end

while wait() do
	local cash = CheckStats()
	AmountOfCash = cash
end

Player.leaderstats.Cash.Changed:Connect(function(amount)
	local number = CheckStats()
	
	local ReplicatedStorage = game:GetService("ReplicatedStorage")
	
	local Modula = require(game.ReplicatedStorage.AbbreviateNumber)
	local text = Modula:Abbre(number)
	
	script.Parent.Cash.Text = text
	print(amount - AmountOfCash)
end)

No need for snark in your title, or for demands.

The problem is that when loops run and they stop everything after them from running since Lua runs from line-to-line. You should learn about coroutines or spawning threads.

The solution is simply this:

local f = coroutine.create(function()
	while wait() do
		-- do stuff
	end
end

coroutine.resume(f)

You MUST put the while loop at the end. Because the script will be on repeating that loop, and will not go the next line of the script.

The only way to get the code after the while loop is to have some kind of breakout aka:

local doBreak  = false
while true do
	if(doBreak  == true) then
		break
	end
	wait()
end
--// this bit will NOT be execuited unless the doBreak becomes true! otherwise it would be run!
print("hello world!")

to make it easyer i would make changes from:

local Player = game.Players.LocalPlayer
local AmountOfCash

function CheckStats()

    if Player then
        local Cash = Player.leaderstats.Cash.Value

        return Cash
    end
end

while wait() do
    local cash = CheckStats()
    AmountOfCash = cash
end

Player.leaderstats.Cash.Changed:Connect(function(amount)
    local number = CheckStats()

    local ReplicatedStorage = game:GetService("ReplicatedStorage")

    local Modula = require(game.ReplicatedStorage.AbbreviateNumber)
    local text = Modula:Abbre(number)

    script.Parent.Cash.Text = text
    print(amount - AmountOfCash)
end)

To:

local Player = game.Players.LocalPlayer
local AmountOfCash

function CheckStats()

    if Player then
        local Cash = Player.leaderstats.Cash.Value

        return Cash
    end
end
--// moved this before the while loop so it gets hooked up
Player.leaderstats.Cash.Changed:Connect(function(amount)
    local number = CheckStats()

    local ReplicatedStorage = game:GetService("ReplicatedStorage")

    local Modula = require(game.ReplicatedStorage.AbbreviateNumber)
    local text = Modula:Abbre(number)

    script.Parent.Cash.Text = text
    print(amount - AmountOfCash)
end)

while wait() do
    local cash = CheckStats()
    AmountOfCash = cash
end

for the code you posted to work after the while loop you would need some way of breaking out of the loop but then re-call the loop after you hook up the event for your cash. something like:...

local Player = game.Players.LocalPlayer
local AmountOfCash

function CheckStats()

    if Player then
        local Cash = Player.leaderstats.Cash.Value

        return Cash
    end
end
--// ##################################
--// changed/new code
--// ##################################
local FinishedLoading = false
function mainLoop()
	while wait() do
		local cash = CheckStats()
		AmountOfCash = cash
		if(FinishedLoading == false) then
			break;
		end
	end
end
mainLoop()
Player.leaderstats.Cash.Changed:Connect(function(amount)
    local number = CheckStats()

    local ReplicatedStorage = game:GetService("ReplicatedStorage")

    local Modula = require(game.ReplicatedStorage.AbbreviateNumber)
    local text = Modula:Abbre(number)

    script.Parent.Cash.Text = text
    print(amount - AmountOfCash)
end)
FinishedLoading = true
mainLoop()
--// ###################################
--// End of new/changed code
--// ###################################