Before learning machine learning i should learn python or python3 or cpython

Answer 1

Python3

Answer 2

First of all, python and cpython are mostly the same thing. The most common implementation of python is cpython.

Second, you can start learning ML without Python because the important part is understanding the concepts. But it would be better if you had a language at hand in which you could implement what you learnt and see it in action

Answer 3

Python 3(3.7.8) is the latest version as of now.
Python 2 is no longer supported since 1st January 2020
because it was not able to handle improvements made to it.
Try reading this article, you'll get to know about it:
https://www.python.org/doc/sunset-python-2/

Coming to your main question:
Python is a very good choice and often recommended for machine learning. So, you can start learning python before machine learning (as I suggest).
Also,look for others opinions if you want
https://www.sololearn.com/discuss/1200784/?ref=app
https://www.sololearn.com/discuss/1464050/?ref=app
https://www.sololearn.com/discuss/797564/?ref=app
https://www.sololearn.com/discuss/1213794/?ref=app
https://www.sololearn.com/discuss/1440644/?ref=app
https://www.sololearn.com/discuss/1698989/?ref=app
https://www.sololearn.com/discuss/1664974/?ref=app
https://www.sololearn.com/discuss/854119/?ref=app
https://www.sololearn.com/discuss/1006081/?ref=app
https://www.sololearn.com/discuss/956864/?ref=app