Grid Tools
The Grid Tools button group contains two buttons which you can use to either create an Easy Grid (to quickly set up and test simple modeling, upscaling, and reservoir simulation scenarios), or to extract a horizon to create a tri-mesh from a 3D grid layer, which can then be used in the application as any other horizon.
For more information, see
Creating a simple geological model with an Easy Grid
Extracting horizons from K-layers
For how to edit properties of your grid cells with the Editing Tools, see