hii Dheeraj ,

Instrumentation engineering is the branch of engineering that specialises on the principle and operation of measuring instruments that are used in fields of design, configuration of automated systems in electrical, pneumatic domains . The  required tasks are very domain dependent; instrumentation engineers typically work for industries with automated process with the goal of improving the productivity, reliability, safety, optimisation and stability. Instrumentation engineers are commonly responsible for integrating the sensors with the recorders, transmitters, displays or control systems. They may design or specify installation, wiring and signal conditioning. They may be responsible for calibration, testing and maintenance of the system.

For scope and further study visit -  https://www.google.com/url?sa=t&source=web&rct=j&url=https://engineering.careers360.com/articles/instrumentation-technology-0/amp&ved=2ahUKEwj3sMC80_DiAhUBQ48KHU0nD40QFjAgegQIARAB&usg=AOvVaw2yEwU0qIMufEjuictiadGy&ampcf=1

Hope I resolved your query .