How to execute .py python program on python software?

Answer 1

You can either associate .py files with an IDE like e.g. IDLE so that when you double click a .py file, IDLE is started and you can run the script by pressing F5. Or you can run the program via the terminal/console with "python myfile.py"

Answer 2

If you have problems whit the python command you can specify the version of python you are using, for example python3 my_game.py