Hello @GokulakannanV
For customizing the share link dialog, you can begin by exploring the following locations:
/libs/dam/gui/content/adhocassetsharepage/
/libs/dam/gui/coral/components/admin/adhocassetshare/clientlibs/adhocassetshare/js/adhocassetshare.js
These areas should provide a good starting point for adding custom columns in the share link list view