import tkinter
from tkinter import *

win = Tk()

frame = Frame(win)
frame.pack()

frame2 = Frame(win)
frame2.pack(side = BOTTOM)

rb = Button(frame, text = 'red',fg='red')
rb.pack(side=LEFT)

bb = Button(frame, text = 'black',fg='black')
bb.pack(side = LEFT)

blb = Button(frame, text = 'blue',fg='blue')
blb.pack(side = LEFT)

gb = Button(frame2, text = 'green',fg='green')
gb.pack(side = LEFT)

win.mainloop()