As such you dont have any Competitive Examinations or Olympiads, but you do have mamy Industry Competitions sponsored by various Industries like Flipkart, Bajaj, Tata Steel, GE and others. Winning such competitions, not only gives you a Acclamation and Accolade, but in many cases being among Finalists or Winners gives you a chance to secure a PPI/PPO.

Besides these, there are many Inter College Competitions, which are highly interesting.

Secondly, if youre into Coding, Data Analytics and Technical Stuff like CAD/Design, Robotics, there are lots of Opportunities including Hackathons, Competitions and Events.

Of couse, in later years of Preparation, you may prepare for Competitive Exams like GATE, CAT, UPSC ESE or if youre into Finance, maybe for CFA/CFM.