To make all of the pages in your website "identical" in structure you should:

• Go to the Admin, Site Settings page and select a default skin and container for your site.
• Go the the Settings for each page and make sure that the Page Skin and Page Container are set to <not specified> under Appearance in the Advanced Settings part.

You can always specify a skin or container for those pages that you want not to follow the standard.

For modules that you want to appear on every page, go to Settings for the module.  Under Advanced Settings, check the box to have the module appear on all pages.  If there are pages where you don't want a module to appear, go to that page and delete the module from the page. 

To add a new module to the right pane of every page, add it on the home page, and then check the box on Settings for that module.