Python program not working from start

Hi all, I’ve been trying to get Python up & running on my laptop for a week! I can’t get past basic premises. I’ve uninstalled completely & reinstalled but when I begin basic prompts after tutorial direction such as …. python3 demo.py …

I am returned with …. Python was not found … etc. Pease help to get off the ground. Thanks

Which operating system?

If you’re on Windows, it’s recommended that you use the Python Launcher py:

py demo.py