Hi Abhishek! Dropper students are asked to submit this type of certificate . I too had to submit this certificate during my admission. You can ask a lawyer to make a affidavit regarding that, he will make one for you at some charge. The affidavit will state the cause of your one year drop.

Dear student, there is no such certificate named gap certificate for taking admission into various institutes in India. You can apply in any institute with the required documents and the qualifications necessary to be allotted a seat in that particular college. You won't face any difficulty even if you are a dropper except in top institutes like IIT and NIT.