No, you can not file RTI to IBPS. The Institute of Banking Personnel Selection (IBPS) is an autonomous body and recruitment body that was started with an aim to encourage the recruitment and placement of young graduates in public sector banks in India, other than the State Bank of India. It also provides standardised systems for assessment and result processing services to organisations.
Since, it is an autonomous body. Therefore, it does not comes under the ambit of section 2(h) of the RTI Act'2005. Hence, You can not file RTI to IBPS.