You will learn you cannot save the world. I ask, "save it from what?" That statement is not meant to discourage, but to encourage your perspective. Despite, I have always been amazed how one person can make a positive difference to whom they encounter. I am rooting for you!
Never fear, luv. Mother Nature will shake us off the planet like so many fat fleas. The earth will survive quite well without the pestilence of humanity. ;)