The Select button under Object font lets you choose the default font to be used for objects. Under Color preferences, you can specify the border and the filling for objects.
New objects will be created according to these settings. However, you can change the settings later individually for each object.
When you start a new project, it's a good idea to configure these settings using suitable values to keep the effort required for making manual changes to a minimum. The settings only apply for the current project.
The Default parameter in the respective object properties (Font/Frame/Background) is active as standard for all objects. Therefore, if the default values are changed later, this will also affect all objects whose font has not been changed manually.