Yes, you can file RTI to Goa Shipyard Limited.
Goa Shipyard Limited (GSL) is an Indian Government owned Ship Building Company requisitioned to manufacture warships for the Indian Navy and the Indian Coast Guard. GSL is a Public Sector under Ministry of Defence. Thus, GSL 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 Goa Shipyard Limited (GSL) by paying the prescribed fee.
To know the further procedure for filing RTI's for Central Government please check https://onlinerti.com/how-to-file-rti-online-for-center