Don't get confused . As you have selected the exam center , you will have to go there on your examination date. When  you will reach at your examination center , you will have the answer the questions on the computer provided by the center . These is called online mode examination. I hope your doubts are cleared by now. For any further queries , you are free to write your doubts in the comment section below.

Hi Sreelkashmi

It means the exam will be computer based only but you have to go to the particular exam centre where you have to give this exam. They have computers installed there.

Hope this clarifies your doubt :)