tkinter checkbutton if checked

[MC2020]

Hi - I am learning python and need help with this code. I have researched online, but haven't been able to find an answer for what I'm looking for.

My code is below. The 'open' function is what I need help with. I am looking to add the fooditem selected to the newwindow if the checkbox is checked. My code is below but isn't working. Can someone help point me in the right direction?

fooditems = ['pizza','breadsticks','wings','CocaCola','brownie']
fooditems2 = []
price = ['15', '5', '10', '3', '2']
quantity = ['1','2','3','4']

import tkinter as tk
from tkinter import *
from tkinter import ttk

menu = Tk()
menu.geometry('500x300')

combobox = ttk.Combobox(menu, values=quantity)

def Open():
    New_Window = Tk()
    New_Window.geometry('500x300')
    calculateButton = tk.Button(New_Window, text = 'calculate')
    calculateButton.place(x=250,y=250)
    for x in range(len(fooditems)):
        if Checkbutton.get(x) == 1:
            fooditems2.append[x]
    fooditems2.grid(column=0, row=x)
    combobox.grid(column=15, row=x)
    New_Window.mainloop()


for x in range(len(fooditems)):
    a = Checkbutton(menu, text="", variable=fooditems[x], onvalue = 1, offvalue = 0)
    b = Label(menu, text=fooditems[x])
    a.grid(column=0, row=x)
    b.grid(column=5, row=x)
    
    

confirmButton = tk.Button(menu, text = 'Confirm', command=Open)
confirmButton.place(x=250,y=250)

menu.mainloop()