Is Opening Up a Business a Secure Way to Earn Money?

I am sixteen now and am thinking about careers. I may go into sales, insurance, accounting, you know a nice relaxing, well paying office job. I was wondering if taking out loans and open up a business in agriculture sales. (I heard that's a BIG market and I go to an agriculture high school) Selling feed or something like that. Do you think opening a business is a secure job?

Suggestion:

80% of small businesses fail within the first 5 years of business. In order to be successful, you certainly aren't looking at a nice relaxing office job – figure working 60 to 80 hours a week to start with lots of anxiety over paying bills, etc.