Hello Aspirant,
Hope you are doing great. For UPSC CSE, candidates must be at least 21 years old and under 32 years old for students in the general category, with some age restrictions being relaxed for those who qualify for a reservation. Given that you said that your date of birth is March 5, 2003, you will be 21 years old by the first quarter of 2024, making you eligible to take the exam.
You can refer the below link for more details:
https://competition.careers360.com/articles/upsc-ias-eligibility-criteria
ALL THE BEST
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