How to add keyframe animation to an imported FBX.

Hi All,

I would like to ask your help, because I'm new in Unity. Is there any way to implement a method in C#, which can create an animation from a keyframe, and attach to a gameobject ?
And what is the hierarchical order of an animation? I have some question marks in my mind:

GameObject - Animation - AnimationClip - AnimationCurve - Keyframe

Is this the right order?

Extra note: The gameobject imported from an FBX file, it's a simple cube at the moment, but I'm planning to replace it with a detailed one, but this will be the next step. :)

Thanks in advance, Tamás