How do I use an if statement to check if a part has been clicked?

How do I use an if statement to check if a part has been clicked on? I'm using an If statement because... I really don't know how to explain it you'll understand when you read the script

local chat = game.Workspace.Dummy1.Head.Dialog
local Menu = {"pizza","fries","hamburger"}

local Item = math.random(1,#Menu)  -- chooses random Item from the table

chat.InitialPrompt = (Menu[Item]) -- says random item

local PizzaButton = game.Workspace.PizzaButton -- a variable for the button
local FriesButton = game.Workspace.FriesButton -- a variable for the button
local BurgerButton = game.Workspace.BurgerButton -- a variable for the button

if chat.InitialPrompt == "pizza" then -- checks what have random item has been choosen
	print("Pizza has been choosen")
	if  -- Here I want to check if a button has been clicked
elseif chat.InitialPrompt == "fries" then -- checks what have random item has been choosen
	print("Fries has been chosen")
	if -- Here I want to check if a button has been clicked
elseif chat.InitialPrompt == "hamburger" then -- checks what have random item has been choosen
	print("Burger has been choosen")
	if -- Here I want to check if a button has been clicked
else
	print("Error")
end

I hope you understand I'm not really good at explaining.. Also it is NOT a gui

Edit: Ok I am trying to make something like pizza place where the customer orders something random and you have to press a button so you could complete the order I hope this makes it easier to understand :)

Looking at your scrip i think its a click detector you are talking about. So I think we will have to alter your script a bit. Instead of using if statements, you can use functions!

so you want to insert a click detector in your pizza fries and burgers. then create a function for each of them!

heres a function for fries:

local clickDetector = workspace.fries.ClickDetector -- make sure the object is called fries
 
function Click()
	print("EAT DA FRIES")
end
 
clickDetector.MouseClick:connect(Click)

If your button is a GUI you should use MouseButton1Click:

script.parent = friesbutton -- rename your gui into friesbutton
function clickfries()
  print("EAT DA FRIES")
end

script.Parent.MouseButton1Click:Connect(clickfries)
-- DO NOT ADD A CLICK DETECTOR FOR THIS SCRIPT THE GUI IS ALREADY A BUTTON

Hi I think you should insert a ClickDetector in the part and then do this script

local ClickD = --Define Click Detector here

ClickD.MouseButton1Click:Connect(function()
	--whatever u want it to do
end)

btw, this code will run at the specific moment when the button is clicked

OR

if u wanna see if a part has been clicked before in the past, then use this script

local ClickD = --Define Click Detector

ClickD.MouseButton1Click:Connect(function(player)
	player.HasClicked.Value = true
end)

HasClicked is a BoolValue in StarterPack

This code basically stores the value that the player has clicked the part and the value can be used later

hope this helps