I am very much new ti Raspberry Pi.
I have already done light connection to relay it is working without any issue. Now i am unable to do manage with manual switch board.
You need to provide more information about the project. Before someone can help you.
For example, what parts are you using, how did you connect them, ect..
If you want to be able to switch the light on and off from either the manual switch or by the relay then that is exactly the same as the switching frequently seen in homes at the top and bottom of staircases.
The switch and the relay need to have changeover contacts.