For python, you can check out this free course for beginners. You can follow it in an app on your mobile device, or in a browser.
It Goes through Python step by step with community support (comment section in Every step of the coarse), which is helpful if things get hard.
It’s a really good start if you’re unfamiliar with the language and also programming in general.
I liked Sololearn as a place to go over what I got from reading a couple books and other things. It helped with going over the basics.
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There's an r/learnprogramming subreddit, and as far as Reddit, that's a good place to start looking for information.
But the short version of the easiest way would be to pick a language, and find some tutorials (or a book) to start working through. For example, Python is often recommended as a first language, and a couple starting points:
https://www.sololearn.com/Course/Python/
https://www.codecademy.com/learn/learn-python-3
(Python 2 was popular for a long time, but has been falling away for a few years, and Python 3 has really picked up. They're similar in many ways...but different enough that you want to stick to one to avoid confusion).
I've been using Automate the Boring Stuff and the SoloLearn app on my phone for Python.
For C++, I can't help you.