A Cheque Book is a small booklet provided by the bank that acts as an instrument to make payments
You simply fill all the information on the cheque, tear that from the book and either deposit it in the payee’s bank or hand it over to them.

Example:
Suppose you owe 10000 rupees to someone. You can just write a cheque for 10000 and give it to them. They can then deposit the cheque into their bank account and receive the payment.