How to apply for lost community and birth certificate.

For the Birth Certificate, you can either -

1. Go to the State Registration Office of the state where you were born and apply for issue of a birth certificate informing the office that you have lost the original through an RTI. You may have to get your birth certificate's registration number from the Public Health Dept or any other concerned authority. You will have to furnish a few main documents - 

-Your complete Birth Name
-Your Date of Birth
-Place You Were Born
-Your Parent’s First and Last Names. (Usually including your Mother’s maiden name)
-You will need to state that the replacement record is for you as you cannot request a replacement of someone else’s records.

- you will have to pay a fee in addition/get a stamp.   

OR 

2. You can apply for a copy of your birth certificate online too. This link will help you through the same -( https://delhi.gov.in/wps/wcm/connect/DoIT/delhi+govt/birth+certificate/birth+certificate ) You have to file an affidavit for reissue in the same manner.

You will have to fill a form with all the correct information and after a verification, you will be sent your certificate by post.

Now, Regarding the Changes in the Birth Certificate - 

Go to a municipal office near you. Take the application form regarding the name change.

Go to a local notary and make an affidavit. Specify the strong reason for the change of name. This affidavit is used for changing the first or last name or complete name. After the affidavit is prepared, submit it at municipal Office along with the old birth certificate ( In your case, you will have to get a new one reissued first), address proof, remaining proofs as well. Within 15 to 20 days, you will get your new birth certificate.

OR

You can even get the corrections done online through this link - https://tg.meeseva.gov.in/DeptPortal/Meeseva-Applications.html

• Click on tab “GHMC”
• Here you will get a drop-down list of about 7 choices
• Click on the option “birth-death corrections”

For the Community Certificate, go to the authority that issued the original certificate and either just apply by the way of an affidavit or an RTI. You will have to fill up a prescribed form and show identification documents for verification and then you will get the certificate issued. If you have a xerox of the community certificate by any chance, take it along. I hope this will give you an idea. Please feel free to ask further questions if any!