Most of the unstable systems exist in the chemical process such as bio-reactor, distillation column, CSTR, fluidized bed reactor. The control of the unstable systems was very difficult due to their multiple steady states, complexity, and dynamic behavior. There are several methods available in the literature for identifying and controlling unstable systems. But all these methods require extensive mathematical complexity and in-depth knowledge of the processes. Moreover, there is much more complexity associated with identification and controller design for multiple-input and multiple-output (MIMO) systems using the conventional methods. In the present work, we are incorporating the simplest method for identification and control the unstable systems using the modified relay feedback approach along with one data-driven approach. Instead of using the MATLAB routine for the purpose of identification and controller design, we are trying to identify and control using the new software PITOPS. A data-driven approach has been introduced to overcome the difficulties with conventional methods with the help of PITOPS. A comparative study has been made among the methods proposed in this work.