I think almost everyone has dreamed at some time of writing a best seller, becoming famous and wealthy, winning a Pulitzer or becoming the next J.K. Rowling. Whoever is fairly literate at least. It´s not impossible, of course, but unlikely; you probably have the same odds of gaining fame and fortune writing as you have of winning the lottery.
But, as with all worthwhile things, constancy and effort will pay off. If you decide to start writing as a means of earning your living, you must take the plunge, start writing, finding your writing markets, submitting your articles to these markets, and wash, rinse, repeat. Once you train yourself to write regularly, you will see your production, your income and your self esteem grow.
You will find a lot of allies on the way, Ruth Barringham from writeaholics.com, Angela Hoy, from WritersWeekly.com, Yuwanda Black at InkwellEditorial.com, yours truly and so many others.
It´s a long, often frustrating, sometimes nerve racking, always thrilling ride, but the pot of gold is at the end of the rainbow. If you can give yourself the gift of discipline, which is essential, and allow your muse to run free, you can achieve your goals in less time than you would expect.