I have a full-time job, outside of the STEM industry. I want to make extra money on the side, and i see people that work as programmers or just generally involved in software development get to have jobs as a part-time, and they fairly do well for themselves. So i want to learn and gain skills related to that subject. My question is i hear about fullstack, java, python or frontend/backend developer etc, and generally speaking i know what they are but i wanna understand which of those i can actually take the time to learn and potentially get a part-time role as. Thanks