Make data for Find differences between two pictures game

I am going to make data for Find differences between two pictures game by OpenCV python
Input: an image
Output: an image with different points
Have any idea for this task? I am stuck

problem: you’re far too vague.
what exactly are you looking for ?
as long as you cant specify that, you wont find an answer
(and we won’t even bother …)

no, you never started thinking…

I mean I am making a program that when we have an input image, we can get an image with different points. This is making data for “spot the differences” game data. My English is not good so maybe I write a bit vague. I’m sorry about that :((( And I really tried to think but I can’t find a way. Thank you for replying me. If you have any ideas, can you help me?

https://docs.opencv.org/4.x/d6/d00/tutorial_py_root.html

come back, if you have any own effort to show.