I won't like to do a ditto copy of other book, but I would like to write a book on any of the following topic.

a. evolution of feather
b. the blue moon
c. Interiors of sun

Please guide me accordingly, about book writing starting tips etc,because before this I have never tried to write a book, is all books are required to get a ISBN number, and how the book can be register there, lot of questions are there in my mind.

would you like to share any ideas!

is there a ready made software to write book which will enable to check out the mistakes and gramer and composition!