Hello, @sachin_sharma
I would suggest trying the following.
First step: Try CTRL + F in Word with the initial text ( NA
NO:7 WHITES ROAD
CHENNAI
Chennai, 600014 India)
as input to see if the text is matched fully.
Second step: Install UiPath.Word.Activities and use Replace Text activity (inside a Word Application Scope). Write the text to be replaced in the Search field and the desired new text in Replace field.