This will list the element types that can be chosen. For the present example we will choose the default Quad4 elements. This is the 4-noded quadrilateral element. Then click on the Apply button. The mesh should now be generated and displayed.
White lines indicate the element boundary.
The numbers in white are the element numbers and the ones in red are the node numbers. There should be 25 elements and 36 nodes in the mesh. The opposite sides in a surface are meshed identically. Then re-create the mesh.