Hrusikesh,
I'm a end user of SAP FI for more than a year & i'm very much familiar with the UI (screens & there functionality).
You are very right that i have to go for FI first & CO afterwards; one of my friend is a FI CO Consultant & he have shared multiple video lectures with me related to the two modules.
Please could you further elaborate your suggestion of FORMAL TRAINING !!!
Thank you
Mirza