The other content on contact us page is dynamic. It shows the details of your hotel your enter at the back end.
The Navigation Menu cannot be edited to right now in QloApps v1.3.1 but in our next version which is going to release soon, you will have the option to edit the navigation menu.
If you want to edit the navigation menu then you will have to make the changes in the core files
To add Google Maps
First, you will need to Hotel Reservation System--> Settings --> Hotel General Settings