Hi,
I hope you doing good and preparing well for your placements.
It depends from college to college, how they are providing the ways to contact with administration and placement cell. As you haven't provided the sufficient information, it is not possible to answer the query for your perticular college.
However, I will suggest you to visit your institution website, and find the contact us option. More than this, if you have your college registrar email, it will be a great help for you.
I suggest you to talk to your seniors/friends about the placement cell, they will be definitely able to guide you with the actual process. More than this, if you have physical access to your college, I suggest you to visit physically to the placement cell, and ask your doubt to the employee sitting there.
I hope it helps.
Thank you!