GeoGebra allows you to change and save settings using the Options Menu. For example, you may change the Angle Unit from Degree to Radians (GeoGebra Desktop Version only), or change the Point Style, Checkbox Size, and Right Angle Style. In addition, you may change how Coordinates are displayed on screen and which objects are labeled (Labeling).
Please see the section about the Options menu for more information.
You can save your customized settings by selecting item Save Settings from the Options menu. After doing so, GeoGebra will remember your customized settings and use them for every new GeoGebra file you create.