Dear anjani!

For UP board exam you do not have to apply yourself instead you need to get get admission in a school that is recognised by UP board. They will register you and you will have to submit relevant details and documents for registration in class 11th.

Then in class 12 there will be a centralised board exam for all UP board candidates and the admit card will be provided by school itself.

Therefore , in a nutshell you do not have to anything on your own your school will take care of all the registration and application for board exam you just need to comply with the school.

Thankyou!