Well, to start off, i am 14 and have a great passion for writing! i really need to know what are the main points of writing a fiction book and creating characters?
You must master the English language. Especially you must master prose. This means grammar, vocabulary, sentence and paragraph structure, rhythm and balance. Then you must have an interesting story to tell, a vital question to answer or an issue of value to address.
For character development you need to have a good grasp of human psychology, both normal and abnormal, because your heroes are not all good and your villains will not be all bad. But they must be believable and consistent in their actions, unless your story gives them a very good reason not to be so.
When you begin writing, do not edit or proof or allow anyone to read it until it is complete in rough draft form. Allow your characters to come as they will and, by all means, allow them to help you write the story. Let them tell you who they are and what part they will play. Do not try to be too contrived.
Above all read, read, read and read the fiction masters beginning with James Mitchener, Pat Conroy, Helen Hunt Jackson, Marjorie Kennan Rawlings and Louis L'Amour. These are easy reading, but great teachers. Later, when you are a bit older read the classics. One of the first classics I read was Silas Marner. I thought it would be boring and was totally surprised at how compelling it was.
Begin with short stories and then progress to novelettes and then, by and by, a novel. If you go to University and still want to be a writer,study English Literature, creative writing and psychology.
Good luck and happy writing,