Hello Aspirant,
The admission process for droppers in IITs, NITs or any other engineering colleges is exactly same as that of students giving it for the first time. However, do note, most colleges allow only 2 year of break and not more. For example if you passed your 12th in 2021, then you can give JEE in 2021, 2022 and 2023. After that, you will not be eligible to give the test.
Hope this was helpful.
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