Hi,
The Manage Page area lists only those pages you created in WordPress. The home page is by default a dynamically-generated page of your latest posts.
To do this, by default the home.php file will be loaded when visitors access your home page. If that file is not available in your theme folder, then WordPress runs the index.php file.
Alternatively, you can specify a static page as your home page by selecting Settings – Reading in the WordPress Admin panel and selecting A static page radio button. From the drop-down list box, you will need to select one of the pages you created (i.e. pages that would be listed on the Manage Page area) to serve as your site’s home page.
You don’t mention whether it is the name of the page (i.e. what appears in the web browser title bar) or the URL itself that you would like to rename.
All the best.
Vaughan