volume mesh instead of surface mesh Octree method
 

I imported geometry from ANSYS design modular. I have performed 3D boolen operation on the geometry as well in Design Modular but when I mesh in ICEM using OCTREE method all I get is surface mesh. How can i get a volume mesh?

PS: I am following steps as instructed in Tetra/Prism Mesh Generation for a Helicopter. I tried to manage using cut plane where i can only see meshes around surface