Help: Layers Interface
The Layers 
button brings forward the Layers window.
If no Grids or Shapefiles are loaded then this window will pop up:
Click the folder icon 
and a select layers window will appear, where you can load available data.
The Layers button brings forward the Layers window.
If no Grids or Shapefiles are loaded then this window will pop up:
Click the folder icon and a select layers window will appear, where you can load available data.