I am very biased to answer that mathematics drives science. Advance the tools and applications follow. [1]
Here is a more heuristic take on it by Elon Musk: https://www.youtube.com/watch?v=tnBQmEqBCY0
2. Work one-on-one with another person. Someone helped you. Now you help someone else. Then another. The ego says you must impact millions. Truly, you will do more by changing one person's life. Then another. The chain reaction will take effect.
3. Serve a small group in your community. Be a worker among workers. A friend among friends. Don't go for glory. Don't try to be the Big Cheese. Be there for service to make the organization better.
Your work can be a channel for these efforts. So can being a spouse and a parent.
Everyone wants to be Steve Jobs or Bob Dylan or Martin Luther King.
Just be a good dad. There is a universe of value in that.