Ok,
You need to work with categories, posts and custom menus.
lets suppose you’re making a site for food lovers
So go into Dashboard>posts>categories and create a category for your page 3 (eg recipes) and then make another for your Page 4 (say cooking tips)
The against each post you write as you edit it you’ll see on the right hand side a categories area, so you can you add it to either say recipes or cooking tips.
Then go into Dashboard>custom menus. On the bottom right you’ll see categories, and you can add the recipe and cooking tips categores to the menu.
That will fix what you want for page 3&4
For page 2, there are several ways to achieve this.
To do what you specifically ask, you’d need to create some code, and I suspect that this is beyond what you want to do, so I’d suggest you forget page 2 for the moment, and achieve this another way, which I’ll cover next.
So now to you need to go into dashboard>appearance>customise
At the bottom of this list on the left, you’ll see options for the static front page. this will tell you whether you’re currently using a blog page or a static page, and if static page what it is called.
If it is already a static page, then you can simply edit and change the one it tells you it is using.
If it is a “your latest posts, then go into dashboard>pages and set up a home page called “welcome” with whatever content you want, and then go back into this customise area and set the static front page to this.
So you now have a static front page, and pages 3 & 4 showing their respective categories.
To fix your “page 2”, I’d suggest you use a sidebar on your home page, and add the recent posts list, this will let you select how many stories to show
to get an idea what this may look like see
http://www.gospbc.co.uk
The “latest news” on the right is in a widget showing the most recent 7 stories
