How to make tkinter's GUI components dynamic?

You can do what you want by binding an event-handling function so it will be called whenever a root window <Configure> event occurs. This will allow you to change the size of the image attached the Label whenever the root window is moved or resized.

In the code below, the Pillow fork of the PIL (Python Imaging Library) is used to do the image resizing since tkinter doesn't provide a native way of doing it. The original image is stored separately and all scaling that needs to be done placing it on the Label is always relative to its size. This prevents errors from accumulating and degrading the image displayed.

Note I also changed your from tkinter import * to import tkinter as tk because there was a conflict between a tkinter.Image and a PIL.Image. It's generally best to avoid import * prevent this from happening anyway.

from PIL import Image, ImageTkimport tkinter as tkimport timeDIMENSION = 800, 500def config_callback(event):    global bg    window_w, window_h = root.winfo_width(), root.winfo_height()    # New height of image is original height * ratio of current to starting size of window.    new_height = round(orig_height * (window_h/DIMENSION[1]))    # Resize original image to this new size (without changing width).    bg = ImageTk.PhotoImage(orig_img.resize((orig_width, new_height), Image.ANTIALIAS))    background.config(image=bg)root = tk.Tk()#image_path = r'C:\Users\Hunter\Desktop\school 1\module\pbm\bg.png'image_path = r'.\bkgr.png'orig_img = Image.open(image_path)orig_width, orig_height = orig_img.sizebg = ImageTk.PhotoImage(orig_img.resize((orig_width, orig_height), Image.ANTIALIAS))background = tk.Label(root, bd=0, image=bg)background.place(x=0, y=0, relwidth=1, relheight=1)root.geometry(f'{DIMENSION[0]}x{DIMENSION[1]}')root.bind('<Configure>', config_callback) # Callback on window move/resizeroot.mainloop()

Here's a screenshot showing what it looks like originally:

Here's another showing what it looked like after changing the window's height: