To pursue a career as an astronaut, especially for an Indian citizen, focus on studying engineering (mechanical, aerospace, or electronic), physics, chemistry, or medicine, as these fields are highly valued by NASA. Height is not a significant barrier, and being shorter may even be advantageous due to lower payload requirements. While flight experience is typically necessary for pilots and mission commanders, mission specialists often do not need extensive flight hours, although having basic flight proficiency can enhance your application. Consider obtaining a Ph.D. and logging flight hours, which is most feasibly done through military service. India is developing its own manned space program, which could provide alternative opportunities. Networking with NASA professionals and attending relevant programs can improve your chances of selection. Overall, a strong educational background combined with strategic experience and connections is essential for aspiring astronauts.