I want to open my own yacht chartering co and boat rental co please help?

You'll need to major in Business in school. Then you'll need to have business insurance for the "Yachts" and the business. You'll need plenty of capital to operate the business. If you are operating a "Yacht" company, you'll also need a Captain's License from the USCG Maritime Academy. I don't know what size yachts you're planning on, but you'll need the license in order to carry any pengers.