(scenario1)say I want (defined in angelscript itself) class CAngelClassChild derived from parent class (defined in angelscript) CAngelClassParent , then i undestand that it is possible to do the inheritance.

(scenario2)
BUT if I have a class CClazzChild (in C++) which is inherited (in C++) from CClazzParent (defined in C++)
Now, i have exposed CClazzChild into angelscript as type CClazzChildInAngel
and exposed CClazzParent into angelscript as type CClazzParentInAngel

Then, How to make this inheritence relationship (inheritance done in C++) made explicit in the exposed classes/type inside Angelscript?
That is,What I will have to do so that CClazzChildInAngel is recognised as inherited (sort of) from CClazzParentInAngel

That's covered in the Class hierarchies section of the documentation.