To set the Horizontal Layout, you need to go to:
In this file, you can look for "navigationStyle" property and set the value to "HORIZONTAL_NAVIGATION".
After selecting the Horizontal Layout, if you want to set the Navigation bar of your choice, then you need to go to:
In this file, you can look for "horizontalNavigation" property and set the value as per your choice.
The options for horizontalNavigation property are:-
INSIDE_THE_HEADER - for Inside Header Navigation Bar
ABOVE_THE_HEADER - for Above Header Navigation Bar
BELOW_THE_HEADER - for Below Header Navigation Bar