In order to take admission in aerospace engineering you have to appear for the entrance exam like JEE (Main+Advanced), Amrita and SRM.

To know the top colleges you can refer below

Indian Institute of Technology, Kanpur

Indian Institute of Technology, Bombay

Indian Institute of Technology, Madras

Indian Institute of Technology, Kharagpur

Amity University

Amrita School of Engineering, Bangalore

SRM University

Indian Institute for Aeronautical Engineering & Information Technolgy

Good Luck!!