3d game object

hello
i was working on wikitude plugin for unity. i run sample example of wikitude, it is working. but when i replaced 3d game object of sample wikitude with another 3d object(.fbx file), its not appearing on camera. i want to know how to add 3d object to unity so that it recognise in camera.
thank you
mithun

and also i want to where i have to add c# script file to make object move or to do some actions. when i tried with a script file to move object , it is not appearing on camera view.

So wikitude appears to be an SDK for integrating AR into your Unity project. That’s all well and good. However, you don’t yet seem to have a solid grasp on the fundamentals of Unity.

Have you gone through the official tutorials?