I Have a Question

I want to help people everywhere but dont exactly know where to start. Im joining the military so i guess thats a start but i want to do more and i feel like i need money to do so. Like sheltering the homeless getting people back on their feet and stuff. Work on the problems in the US and then i want to branch out to other countries like Haiti and refugees from syria. I think Africa would be a big challenge but its worth a try. I like seeing other people succeed in life. I like to see people doing better than what they were before. Makes me feel good.