Welcome @CodeMasterX!
In my opinion (your mileage may vary) it is a viable path.
I have a few recommendations but knowing if you are already familiar with another programming language might help me calibrate better what to recommend…
For a great Processing.Py introduction I recommend @tabreturn’s https://tabreturn.github.io/#processing-reverse (or, maybe, long shot, my own github.com/villares/material-aulas if you can read Portuguese). Also, check out https://py.processing.org/tutorials/
For a general (standard) Python intro for someone who has never programmed before I like to recommend: https://greenteapress.com/wp/think-python/
UPDATE: I have seen you profile this might be a bit too introductory for you. You might enjoy the other non-Processing resource automatheboringstuff.com
It is good that you are aware that there are some differences and peculiarities to learning “standard” Python (Python 3 usually the “CPython implementation”). The main difference and peculiarity is that Processing Python mode is based on a particular Python 2 interpreter (called Jython) that can talk to Java and the Processing ecosystem of libraries, but you can’t use most of the modern Python 3 libraries. You can read more about it here: https://py.processing.org/tutorials/python-jython-java/
You might also try the new and very cool Python 3 “implementation in progress” of the Processing ideas! https://github.com/p5py/p5 (here at the forum: https://discourse.processing.org/c/p5py/27)
Good luck, have fun and welcome to the lovely Processing + Python world.
Cheers,
Alexandre