Over the course of a lifetime, people develop a knowledge-base of skills they can sell. Such expertise can be the foundation for a writing business.
Writing is a craft that is easily learned.
Anyone with good reading skills can quickly learn enough to do the type of writing that will sell in today's market. You don't have to be Shakespeare to sell an article to Compunerd magazine. Any and all expenses relative to your writing business are tax deductible. The use of your home as an office can also be written off. If you are interested in getting paid for writing about your life experience, you must do it in relation to what is published in the nonfiction world.