TATA steel have access to the the technology to roll the rails as it has acquired CORUS, the European Steel Gaint a few years back.
But, TATA steel shall have to install a rail mill to roll the rails. (investment of atleast a few 1000 crore Rs)
Moreover bloom casters shall be required to produce blooms which ultimately are rolled into rails, Tata Steel shall require bloom casters in its steel making shop. They may have ti modify the existing casters or install a new caster as well.