Hello,

Submit an application regarding losing of marksheet to the principal of School from where you have passed out the exam. Mention your roll number and passing year there.

When they verify that you have really passed exam you will get a verifying letter from school.

Then with all documents like transfer certificate and verifying letter ,Aadhar card and ids photocopy, go to your respective board. submit your application there. And you will get your lost marksheet’s duplicate copy after some days.

Hope you got your answer.