Change home page to one of the sub pages
Which version of concrete5 are you using?
Remember, if there are areas in one page template that do not exist in another the content in that area will become hidden.
click on the cog icon to open the page settings panel
then if you click on 'Design' you will be able to see the page template being used for that page.
Then, you just need to change your homepage to use the same template as the inner page.
It is the page template you will want to change and not the pagetype.
If they are both the same template then the difference will be page layouts being used in the page.