How to be able writing a novel?

I had the same problem some time ago, I only found links to schools which would teach me writing though my only problem was to make my stories longer... while reading a book I realized that there is a way to make a short story long...

You need a rough idea to start with, that is the short storie. Short stories normally have no chapters but you need to find stories in the story. Don't worry too much if you only find one or two, the new stories you're writing could give you new material for new chapters.

Think about your main characters. Who are their parents? Where are they from? What have they done so far? What are they going to do? Whom do they know from the other characters and whom do they get to know?
Writing short biographies could help. Especially when there are several main characters with similar histories or names... You don't need bio's for characters that occur only a few times even when the character has some importance to the story. But you should have a bio for characters to which you only rely without them ever being an active part like the dead grandfather or someone who lives on the other side of the world.

While writing all the stuff around your story you should collect quite a few short stories which would be the chapters. If it's still to short think about the used language, sometimes it helps a lot to change a word into another or to describe a situation more exactly...

A novel is nothing more than a bunch of short stories;)

its will be difficult for you to start writing by writing novel. why you not start with the easily first as like write a short story? i believe if you are able to write the short story, after few time you will know about the pattern should be. well, you also shoud read more about how to write novel, story or anything related with these things:)

I've started writing for real in November. And it was all thanks to NaNoWriMo ( http://www.nanowrimo.org ). It's an event in which we have to write 50000 words in one month - November. It may seem impossible, or a big waste of time - and you're probably right, but I've done it. To write 1667 words a day you must completely forget your inner editor that says: "Cut the last sentence, you know it sounds bad" or "That last scene sounded really impossible", and concentrate what your story, your characters, your heart is saying. I didn't knew how good I was to translate my thoughts into words. They just flowed away.

I think i can help you with your problem.
A novel, unlike most essays and short stories, comes straight from the heart.
It is the embodiement of something you believe in, and are truly inspired by.
It is in this spirit that you start writing the novel.
you will find that words flow into your mind, and the only thing that you have to do is write them down.That is the beautiful thing about the human psyche. It needs no prodding to do it's work.No amount of force can make it think, make it generate ideas.
That is why you must find a topic that you can relate to.

A novel is only a group of scenarios tied together. I will start with a dozen or so scenarios that I want to include and then figure out how to coherently make them flow. It's that process that turns a short story (which is harder, IMHO) into a novel.