Do you mean you want to become a realtor who helps people buy and sell houses? You won't need to major in RE or go to college for it. In most states a few bucks and a test will be enough to get you a license.
If you do become a realtor, you probably also want to get legal to sell mortgages. That way you earn profits from both the house you helped someone buy and the mortgage they get!
But before you think about giant amounts of money, you might want to check this:
Why most real-estate agents aren't getting rich: http://www.slate.com/id/2124506/
But don't let that stop you. There's something far more effective you can do. If you become certified to work as a real estate agent, you can really work the system in your favor and use your license to get and sell properties for dirt cheap!
I'd recommend you study RE in college. If I went to school for a degree in real estate, it'd be to learn how to buy and sell properties for myself. You don't really need a degree, but you can learn some awesome tricks that will really help you make money on your own properties.
On top of that, if you become legal to sell mortgages, you'll get access to rate sheets. Rate sheets are "industry secrets" *cough* *cough* that pretty much tell you what kind of mortgages lenders will be willing to give you.
You would not believe the mortgages you'd qualify for -- they're way cheaper what mortgage brokers sell you! If you can get access to rate sheets as a mortgage salesperson, you can really push the mortgage agent around and get a good deal on money for property.