Hello student I'm sorry to inform you but you're not eligible as eligibility criteria says Candidates appearing for SSC CHSL is between 18-27 year (i.e, candidates who are not before January 02,1993, and not later than January 1, 2002). So as per this eligibility criteria you're not eligible as you're born ok March 2002.
For more updates refer to the link mentioned below - https://www.google.com/amp/s/competition.careers360.com/articles/ssc-chsl-eligibility-criteria/amp

Feel free to comment if you have any doubt
Good luck

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