Hi Kanni,

To become a scientist after getting into IITs, you will have to do research oriented works during your B.Tech course and have to write some good research articles in famous journals.

You should have passion about researching and finding new and innovative things. that's all. IITs have a much better platform than any other college for research oriented studies.

After graduating from there you can go in ISRO or DRDO as a scientist by clearing the required exams.

Refer here for more info - https://engineering.careers360.com/colleges/list-of-top-iit-colleges-in-india

To know your other best admission possibilities of Institutes & branches in JOSSA & State counseling as per your percentile, You can use JEE Main College Predictor tool given below

https://engineering.careers360.com/jee-main-college-predictor?icn=QnA&ici=qna_answer

Feel free to ask doubts in the Comment Section.

I hope this information helps you.

Good Luck!