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