Hi Harsh,
Hope you are doing well. Unfortunately, a drop year will affect your number of attempts irrespective of the fact you fill the form or not. You will be left with only one more attempt for JEE Advanced.
Given the fact, you're a 2021 grad, you're eligible to give JEE Advanced in 2021 and 2022 irrespective of the fact you give the exam in 2021 or not.
Hope this helps.
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