Typing Python3 or Python3.6 is giving me an error

Question

I am reading a book("Learn Python 3 the Hard Way") that teaches me python 3.6 but I am unable to get python 3.6 running on the terminal. The book specifically says "In your Terminal program, run python3.6. You run things in Terminal by just typing the name and hitting RETURN." I already installed python 3.6 and Atom but typing in python3.6 is giving me an error.

dyld: Library not loaded: /System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation
  Referenced from: /Library/Frameworks/Python.framework/Versions/3.6/Resources/Python.app/Contents/MacOS/Python
  Reason: image not found
Abort trap: 6

I have tried just typing in "python" but it defaults to 2.7. Please help because I am super confused and I have no idea what I'm doing. Thank you.

Answer 1

Looks like a known bug ; Python versions older than 3.7 do not work on Big Sur.

Answer 2

You should just use the homebrew to install the python or the other packages, it's simpler and doesn't really hampers the underlying versions of python.

If you want to remove the previous versions or unwanted versions from you system https://stackoverflow.com/a/3819829/13176117 this is the best answer that i follow every time.