I need a little advice on the Military.?

I'm 22 years old. I've never had a day of college and I no children. I'm slightly over weight but I'm working towards 160. I'm 5'6. I live in a small town in South Ga and I'm the Manager of a finance company. I'm doing well for myself especially at my age. But, I'm not satisfyed. I'm considering the US Army or Airforce. I want to travel the world. Meet new people. Get a great education and amount to something a little more then small town life. I also want to be in the best physical shape of my life. I want to help make a difference in the world. Not just sponge off of it. Any advice/ comments/ concerns/ doubts/ good lucks would be awesome. Thanks.!