Plugin Pages (how to make pages that are not in wordpress menu)

I’m trying to write an admin plugin which requires multiple pages but those pages do not need to be menu items. I’m finding it difficult to find documentation on the best practices for adding pages.

Additionally, many of the pages will have forms for manipulating data in custom tables in the WordPress database so they will need the ability to process POST data.

The way I see this working is having each of the plugin’s pages show the plugin’s own navigation. How can I link to other pages in the plugin? Do I still make the pages the same way as I do when adding them to the menu?

function my_plugin_sub_page()
{
   // page content
}

Any links, comments, or suggestions are appreciated. Thanks!