Foreign Nationals coming to India are required to possess a genuine and valid national passport or any other internationally recognized travel document establishing his/her nationality and identity and bearing photograph of the foreigner.
Nepal and Bhutan nationals if entering India by land or air from the Nepal or Bhutan border respectively do not require a passport for entering into India. However, they are required to possess, authorized identity proof. Further if they are entering India from a place other than their own country then possession of their national passport is a must.
For more information, visit: https://mha.gov.in/PDF_Other/AnnexI_01022018.pdf