Code

def plus():
    n1 = int(entry1.get())
    n2 = int(entry2.get())
    result.config(text=str(n1 + n2),background="yellow",fg="red")
def minus():
    n1 = max(int(entry1.get()),int(entry2.get()))
    n2 = min(int(entry1.get()),int(entry2.get()))
    result.config(text=str(n1 - n2),background="yellow",fg="red")
def multiply():
    n1 = int(entry1.get())
    n2 = int(entry2.get())
    result.config(text=str(n1 * n2),background="yellow",fg="red")
def divide():
    n1 = int(entry1.get())
    n2 = int(entry2.get())
    result.config(text=str(n1 / n2),background="yellow",fg="red")
import tkinter as tk
window = tk.Tk()
window.resizable(False,False)
label1 = tk.Label(text="số thứ 1")
entry1 = tk.Entry()
label2 = tk.Label(text="số thứ 2")
entry2 = tk.Entry()
plusButton = tk.Button(text="Cộng (+)", command=plus)
minusButton = tk.Button(text="Trừ (-)", command=minus)
multiplyButton = tk.Button(text="Nhân (*)", command=multiply)
divideButton = tk.Button(text="Chia (/)", command=divide)
result = tk.Label()
label1.grid(row=0, column=0)
entry1.grid(row=0, column=1)
label2.grid(row=0, column=2)
entry2.grid(row=0, column=3)
plusButton.grid(row=1, column=0)
minusButton.grid(row=1, column=1)
multiplyButton.grid(row=1, column=2)
divideButton.grid(row=1, column=3)
result.grid(row=2, column=2)
window.mainloop()