How to change menu in Google Website

Step 1: From header section, select the top secion near the title of page element , an wheel icon will appears click over as following animation shows. 

Step 2: Will appears two modes, the first mode is the standard one which is called "Top Navigation " as following 

while second one will be the following mode  which is call " side menu "

And that how to choose type menu, in next post will discuss publishing google site.