Im interested in writing and hope to be an author. what was americas youngest author that had a published book?
Let me tell you from experience: start now. It can take YEARS to get anything published, so if you have any ideas now, write them out in chapters, then go back and rewrite them and start submitting the manuscripts to the publishers(check the company's policy, and only go with ones that allow you to submit drafts to other companies simultaneously.)
From there, keep rewriting. Every time you rewrite, it gets better.
I remember seeing kids as young as 8 years old on the talk shows that write childrens books.
Read this article about the youngest authors in the World :)