Which is the best way to NASA?

I am very fascinated by robots and designing machines with interesting circuits. I want to work with NASA and design robots and other mechanical instruments except Spacecrafts. Which degree is best and which field of engineering is best for it. I also wanted to know if their is any way i can get a degree in both astrophysics and engineering because i love engineering as well relativity and quantum mechanics. I know im very demanding but can it possible. Please tell the complete path after XII cl as i m in india and Want to complete my education in here.