Hi,

When a  student drops one or more year for entrance exam preparation, they are asked for Gap (Year gap) Certificate or GAP Year Affidavit.

It is a declaration that you did not take admission to any other college or university during the year gap.

Buy stamp certificates from any registrar offices or courts.
Then you can contact advocates or officers in charge nearby who will prepare the gap certificates and hand it over to you.

Hope this helps!