Please ask this qurstion elaborately because we are not understanding which exam you are talking about.If you are talking about jee main then you can download your admit card now from there official website.

Hi, if you have to download the admit card than you should go to the site of which you have filled the form. Than if admit card of an exams are released than there must be link given. Than after clicking on the link and filling all the credentials you can login into your account and download your admit card.
Thanks and best luck for your exam...

Hii..
Please visit the official website of that exam/college where you had filled the application form.There you will find a link to download the admit card (if it is released).If you are talking about JEE Mains,then the admit card will be released in the 3rd week of March 2018.For that,you have to visit the official website:-www.jeemain.nic.in
Thanks..!!

First of all go to the official site and check for the date of release of hall ticket, go to the site on the date and there will be official announcement that would be highlighted and will be visible to you,  to download the hall ticket.
Thank you .
Any further query is welcomed in the comments below.

Hello Preethi

Can you elaborate yourself a bit more, for which Exam you applied for ?

Every exam has its own set of rules