HI Saswata,
I have created a simple example and i hope will work for you ,I have taken one screen where i have a text box , button and one webblock. In webblock preparation i have one aggregate which fetches data and show in the grid in the same webblock.
The data will gets filter based on the input you entered in text box in the main screen , i am sending the filter criteria as a input parameter to the webblock.
Please see the attached example oml.
Please mark the answer as solution if it solves your problem.
Regards
-PJ-