Hi @lubna,
Please note that OJS version 3.2 is no longer supported by PKP. I would highly recommend that you upgrade to a later version at your earliest convenience.
The functionality you speak of (adding in particular email variables) is not available in OJS 3.2, but is available in OJS 3.4 and later). For an overview of how this works within specific templates, see this post here: How does the tag {$submissionReviewUrl} work? - #5 by rcgillis
-Roger
PKP Team