divide blog to pages

You can create what are called “category pages.” If I am correct on where you are trying to go from here…

What you want to do is: http://en.support.wordpress.com/menus/

Look through that link. But what you can do is. Go to Post and create a new Category. Remember the name (you can try this for a test). Then go to Appearance and click on Menu. Here is where you can create a navigation bar and menus to choose from and section off your content.

You can create a Menu name which will be your Navigation bar. Then find this under Theme Location to the left of this and set your new Menu name to your primary menu. Then you can add categories to this menu. These categories will act like your pages. You can navigate through them on your navigation bar and post to each section.

When you post something new (Post > Post new) make sure you check the box with the category name that matches the section you want it to go into.