How to write ? How to sell a book ?

This is what i'm thinking about, how can i do that ?

How  about a ebooks, can i write ?

It's so much easy than book rite ?

As far as ebooks go, the first question you have to ask is whether or not the ebook is the format you should be using at all. The humble PDF seems to be the first thing that comes to mind when people consider developing a product, but it’s often the least useful and has the lowest perceived value—at least when you want to charge for it.
People trust Amazon, and whether fair or not, they consider “real” authors to be those who are delivered in ink on dead tree material.

Okay, EBOOKS is really good : why ?

In fact, you can often turn a sweet profit from a document that is only 10, 20 and up to 50 pages long, as long as those pages solve a problem that people will pay to have the solution to.

There are so many ebooks out there that try to tell you that the key to successful ebook creation is “write what you love” and the money will come. They use that angle because that’s what people want to hear, and it sells a lot of ebooks about ebooks. But that doesn’t make it true.
But it all goes back to the fact that you started with a highly motivated person with a problem, and therefore the “instantly downloadable” aspect of the short ebook.