When you click edit mode on an object it comes up with this:
How do I add more lines to the orange area?
When you click edit mode on an object it comes up with this:
shift D (duplicate)
E - Extrude / Shift D - Duplicate / F - Fill
Do you mean subdivide? Press W and click subdivide.
Follow a blender basics tutorial series…
You need some more work on the basics of how 3D works before you try to start modeling something, honestly.