Yes, you can apply RTI to Steel Authority of India Limited (SAIL) .
Steel Authority of India Limited (SAIL) is a Public Sector Undertaking, Owned and Operated by the Government of India. SAIL is the largest steel-making company in India and one of the seven Maharatna’s of the country’s Central Public Sector Enterprises. SAIL comes under the Ministry of Steel. Thus, SAIL is a Public Authority as per Section 2 (h) of the RTI Act 2005 and comes under the ambit of the Act.
Hence, you can apply RTI to Steel Authority of India Limited (SAIL) by paying paying the prescribed fee either Online or by Offline mode.
To know the further procedure for filing RTI's Online for Central Government please refer (https://onlinerti.com/how-to-file-rti-online-for-center)