Ask HN: As a young person, what can I do to make things better?

I am a college senior, and I feel that I and many of my peers grapple with the question of how to make decisions that will allow us to cause positive change. It is not that there is a shortage of problems, but that the path to doing anything about them is so unclear. The most common advice seems to be to "vote with your dollar/behavior", but I struggle with this advice because it's hard to see the connection between small daily decisions and large scale change, and harder to have the discipline make those decisions. With this in mind, I'm curious as to how I can direct my career to put myself in a position to have a positive impact. I am hoping that some of you who are or have been where I am can point me in the right direction.

I am graduating Spring of 2020 with bachelor's degrees in Computer Science and Philosophy from a top 25 University. Next year, I will be working in the Bay Area for a fortune 500 company as a software engineer. I'm excited to work there, and I like the company, but I don't believe my work will have any impact on the problems I care about e.g (education, democracy, and sustainability.) I chose computer science because I believe that the best I could do was to build systems and tools to make positive change easier. Now that I'm this far, I'm not really sure what to do next? What skills should I try to build, technical and otherwise? What kinds of companies do I try to work for? What kinds of mentors do I seek out?