To apply for a U.S. immigrant visa from India, start by determining the appropriate visa category based on your eligibility (e.g., family-based, employment-based, or diversity visa). The process usually begins with a U.S. sponsor (such as a family member or employer) filing a petition on your behalf with the U.S. Citizenship and Immigration Services (USCIS). Once the petition is approved, it is forwarded to the National Visa Center (NVC), which will notify you to submit supporting documents, pay fees, and complete the DS-260 Immigrant Visa Application online. After submitting all required documents, the NVC will schedule an interview at the U.S. Embassy or Consulate in India. Attend the interview with all necessary documents, including your passport, medical examination results, and financial support evidence. If approved, your visa will be issued, allowing you to travel to the U.S. as a lawful permanent resident.