Sometimes making a lot of money and then donating your resources to organizations you care about is a really amazing way to make a difference! But also, wanting to know that your work itself is benefiting the world at large is real. Students are often drawn to thinking about the nonprofit sector when they're interested in making a difference with their computing work, but there are other places that are good for this too. Do your research on companies when you're thinking about where you might like to end up - What are their values? Do they live there? Do their employees live them? What is the work/life balance like?
Besides just nonprofits in general, I'd encourage you to look at smaller companies, those that work in education or healthcare, government areas, and startups that are filling needs in the world.