I do not understand what you are asking here, please provide more details.
2) The public files should not be in the same location as the admin files, these should be in different locations.
3) when uploading to the live server, just like on your local server, the public and admin ages should be in the same location.
I would recommend going to the local library or bookstore and looking up books for getting started with PHP and mySQL for the type of level 1 explanation you are looking for.