Hi @srikavyav, firstly we need two pagelists here, so you can copy the original pagelist before performing the "add" operation and store it in another pagelist.
We now have two pagelists "PL1" and "PL2" so, we can use this OOTB activity "pxCompareTwoPageLists" which compares 2 page lists and determines the changes that have been made based on a specified property ("ID" in your case). Two comma delimited strings of the differences are returned(you'll get your results in Param.elementsAdded).
The other option is, you need to loop inside a pagelist and store the search value in a parameter("ID"). You can use this parameter in IsInPageList funtion and search it in other pagelist.