N.I.O.S board approve by passport office for ECNR clearance??
Yes.. mine got approved and I got ecnr passport. But it was in 2017. I don't know now, maybe they changed it.
Unfortunately, NIOS 10th certificate and any open schooling or distance ducation is not seen as a valid certificate By the passport office.
If you have done any schooling after 10th, that is, any higher studies like 12th board, Diploma, UG, PG, then you can apply.