Hello,

As specified by board once registration is done you can't change it. JEE main Regiistration is used on behalf of JEE Advance so if your JEE main doesn't have the category you want then it won't be changed any more.

So the rank you have got for general category use it for counselling along with TFW. This will help you for not to pay the tution fee to the college where you will take the joining. You can apply for scholarships using your income certificate and your qualifications. Government has done many proposals for YOUNG students of india.

Hope it helps!