[Grace Themes]

Hi Simone,

To show the default home page with all sections as in demo theme
http://gracethemes.com/demo/zeroerror/

First activate the ZeroError PRO theme
Go to Appearance -> Themes and activate the ZeroError theme

Go to Settings -> Reading -> Front page displays
click on radio button of Your latest posts

Please see the documentation, it will surely help you to install and customize the theme.
http://gracethemes.com/documentation/zeroerror/

Regards
Grace Themes