Project Settings
The Project Settings 
option is used to configure the main setup parameters for your RS3 model.
The Project Settings should always be chosen at the start of the modeling, since some of the settings determine the availability and operation of various modeling options. In particular, the number of Stages, Analysis Type, Units, and Groundwater Method should always be chosen before you start creating your model.
The Project Settings dialog is organized into the following sections (pages), which are accessed by selecting the name of the page from the list at the left of the dialog:
Project Settings is available in the toolbar, Analysis menu or default right-click menu.
Whenever the Unit system is changed in the Project Settings dialog, the currently selected units automatically become the default Unit system for all new files.