Can't get started

I am a total noob. starting with Dave’s Python course. Did the downloads and followed his instructions. I think he has skipped over something that might be obvious to you but goes too fast at the start. It says I have powershell… that’s gotta be a thing. then typed in py as he said. not recognised… so I don’t seem to have it installed. Clearly he is excited to be presenting this but it is NOT well explained.

I don’t think I know what course you are talking about, remember we have a lot of tutorials and video tutorials.
You can follow the interactive curriculum for python at