To apply for a marriage certificate in Delhi online, you need to follow a few simple steps through the official website of the Delhi Government. First, visit the Delhi Government Marriage Registration portal. Then, create an account or log in if you already have one. Fill in the marriage registration form with required details such as the names, addresses, and dates of both parties, along with the marriage date. Upload supporting documents like ID proof, photographs, and proof of marriage. After submission, schedule an appointment with the concerned marriage registration office. Once verified, you will be issued the marriage certificate. Make sure all documents are correct to avoid delays in the process.