I already tried to google it but I couldn't find anything ...
I created tkinter canvas with width 800, height 600
apparently, the left upside will be (0,0) 
I want to change left downside to (0,0) 
How can I do this???
You cannot change the coordinate system of the canvas. You can scroll the canvas so that 0,0 is in the bottom left, but the y coordinates will be negative going up.
How can I convert coordinate in tkinter?