Rth or Zth. I need the thevenin resistance and voltage in terms of R C and V1

 

Hi raisal,
Read this AAC Article.

Consider that Vi has been defined as +/-V
E
https://www.allaboutcircuits.com/textbook/direct-current/chpt-10/thevenins-theorem/

 

The best place to start is where you presently are, so what are the steps, as you currently understand them, for finding the Thevenin equivalent circuit (in general)?