To start Python from the command prompt, use the command code example

Example 1: how to execute a cmd command in python

CMD /K - execute a command then remain

import os
os.system('cmd /k "Your Command Prompt Command"')

Example 2: run python program from command line

# press [windows] + [R] (on windows only)
# use the command : cd/the_way_of_your_program
# and now use this command :

py the_name_of_your_program.py 

# don't forget to write the extension (py for python) 
# at the end of your program name