It is complicated. India has at least four language families - Indo-European, Dravidian, Austroasiatic and Sino-Tibetan. So Hindi (I-E) is closer related to English or Greek than to Tamil (Dra), Santali (AA) or Zeme (S-T). While it is rare for people to speak languages belonging to all four families, I know at least three people who can passably speak six languages from two or three families.