Hi Sai Madhu,
I have create an example for you extension and uploaded it in the previous post. In which i am making use of a sheet ID to navigate. Just simple open the development Hub and go to the single configurator. You will be able to find it there.
select your app and then a sheet.
Then in the URL box you will find a URL similar to this.
as you see the the sheet id exists in the URL.
In this case the sheet ID = zpqBGGJ.