I need help, advice with my life, career, dreams! please, any advice will help!?

I am so lost right now. I am pursuing a job in business, sales and marketing, but I really want to contribute to this world. I want to help conserve the rain forest, I truly love nature and hiking and just being one with nature. Where do i start, i'm in college right now, I am thinking about majoring in business and minoring in ...I DONT KNOW thats where i need advice. how can i juggle having a succesfull business career with volunteering in the rain forest, or anything like that. please, any advice, i just dont know where to start!