by mistake my date of birth on the application form of JEE mains is 25.09.2000 but my actual date of birth on marksheet is 29.09.2000 I want to know that there will be any problem in taking admission to any government college because I have scored very good percentile and I have a chance to get an N

Firstly let the counseling starts, after that if you get any seats then go for it. After allotting the reporting centre you must bring all your documents as per mentioned in the provisional admission message to the centre. If you have luck then the person in that centre will ask for you about your mistakes there you can tell them. And the seat will be allotted. But this thing do not happen everywhere. You will be disqualified and will not get any seats. It doesn't matter that you have a very good percentile or rank. You have made a mistake. Or there is one option, that you can mail the jee board stating your issue.