Hi Abdul,
As per your requirement you wanted to add a new column and the value of that column in each row is same so, considering this my soulution are as follows:
1: User Add Data Column activity Processing: 16703913928484959571719374612831.jpg…
2: In properties mention tha data table name and the column header name which you wanted to add
3: In properties ther is one option " Default Value" please mention you default value in that field which will automatically added in all row in that column.
Thanks