What can do for became a chemical eng.
Dear Mohit
You can just have the Zeal to persue that course, that's the only thing you need to have for choosing chemical Engineering.
After completing 10+2/intermediate with 65% in PCM subjects. You can take JEE Mains and after if you qualify that you need to take one more test i.e.., Jee advanced with this you'll get a seat in IIT's if you perform well in those tests.
Or you do have many options like you can take BITSAT, VITEE, Manipal, SRMEE etc.., In these universites after completing written test, you can do take admission in Chemical Engineering Course.
If you need more info, Comment here.
All the best.