Python is one of the most used programming languages in A.I., data science, and backend development.
It is recommended to install Anaconda instead of the official Python for Windows, because it is more stable.
Download the Anaconda version for Python 3.x here.
Install as you would with any other program. Official guide is here.
Ubuntu comes with both Python 3 & 2 installed, so you don't have to do anything.
Install from the official Python package here.
00 - For someone who have never programmed before practicepython.org