Doubt regarding isomers urgent

Bhai maine structural iomerism start kuya hain lekin eo dikkat aa rhi hain ki eo chiz samajh nah aa rhi hain ki ye kese samjhun ki koi do compound sma e hain ki nahi. Aur ye mat bolna ki dekh kar smajha kyuki mujhe samjh nhi aa rh ahain as ye jo maine bola kiy hain usme circle walen area main dichloro nah layenge kyuki vo pehle lag chuke hain lekin pehle wale compound aur ye wala ki shakal toh mil hi nahi rhi hain Teacher:- ns sir. Did iuoac from atp star oneshot 26tard