Astrochemistry by itself isn't a grad program; it would be a concentration in a chemistry or physics grad program which involves the astronomy department, and since astronomy is mostly physics a double-major in chemistry and physics would help a lot. Most astronomy grad students majored in physics. Illinois in america has a good grad astro/chem program. You can do your undergrad degree pretty much anywhere and still get into a good graduate program. actually the best institutes for astrochemistry are in the netherlands/britain / america ... it is still a developing course in india.  These are the some Colleges in India:.

MP Birla Institute of  Fundamental Research Bangalore.

Indian Institute of Science Bangalore Karnataka

Tata Institute of Fundamental Research Maharashtra

Radio Astronomy Center  Tamil Nadu