Taneja's family migrated from Kulachi, in the North Western Frontier Province (now in Pakistan) to Kanpur, India, where his father worked in a sugar mill.
He trained under director Sydney Pollack and Sandford Meisner at the Neighbourhood Playhouse School of Theatre, and learned method acting.
[3] His students included Jaya Bhaduri, Shabana Azmi, Naseeruddin Shah, Om Puri, Shatrughan Sinha, and Mithun Chakraborty.
The faculty included his former students from FTII - Mithun Chakraborty, Benjamin Gilani, Tom Alter, Om Puri,[8] and Geeta Khanna.
Taneja's other students included Parveen Babi,[9] Kumar Gaurav, Sunny Deol, Sanjay Dutt, Govinda, Aamir Khan, Madhuri Dixit, Sunil Shetty, and Ajay Devgan.