Python 3 is the officially-supported version and is the one that is used in the Advanced Laboratories. There are different releases of Python 3 (e.g. 3.8) and it is recommened to use the most recent release, but in particular a release of 3.6 or later.
Anaconda Python Distribution
Anaconda Python is the preferred way to install Python. The distribution includes hundreds of packages including essential scientific libraries including Scipy, Numpy, Matplotlib, AstroPy and more. It is available for Linux, Windows and Mac OS X.
Do not use Python 2!
Python 2 was officially sunset in early 2020.