How can i get bin number.

As you are working in Government organization you have to file Form 24G every month for every type of deduction (i.e TDS - salary/ TDS - Non salary). To file this Form you should obtain AIN (Accounts officer Identification Number). To get the AIN please fill the  "Application for allotment of Accounts Office Identification Number (AIN)"  

Use the following link to get the Application.

https://www.tin-nsdl.com/download/AINapplicationform-03aug10.pdf

Thank you