This depends on the terms and policies followed by your school.
In case you have lost your transfer certificate then you should approach the school authorities requesting them for issuing you a duplicate TC. You may have to submit a written application in this regard to get another TC issued to by your school.
Some schools also requires the affidavit as well as self declaration letter in which you have to mention about your lost certificate.
You are required to approach the concerned principal of the school with an application stating the entire details how the certificate was lost.
You will need to approach the school and give a written request asking for a duplicate copy of the TC to be issued to you.
You will also be required to mention that you lost the TC and require it for seeking admission in college or school.
Also, you need to mention relevant details in the application like your full name, class you studied in etc. You might be asked to pay a small fee for a duplicate copy. The school might also want an affidavit stating that you have misplaced the TC.
You can also advertise regarding the lost TC and also keep the ad paper as a copy with the FIR. Once the file is submitted, the school will provide you with a duplicate certificate of your TC.
Reference: Right of Children to Free and Compulsory Education (RTE) Act