C. V. Raman Global University

First of all my advice to you is don't drop out because drop is not a solution at all. You've scored very well in NATA and even in boards also.
Apply for top colleges who know your luck shines and you get admitted in the top college of architecture.
Apply for top colleges first and then go for average.
All the best for your bright future.
Good luck!

According to the rankings by Indian government and quality of studies obviously, ITER-Bhubaneswar is the best. Indian govt. has given 16 ranking to SOA University (UEM). ITER is also granted second highest NAAC (UGC) CGPA. It has also a good no. of research paper published. Placement there doesn't need explanation. It is claimed to be 90 % above. The minimum package is 3.5 LPA. Professors are said to be best in quality. Many of them are ex researcher from known university from USA and London. So if you want to study, this is one of best place you can especially in this 2 given option of Heritage-Kolkata and UEM.

Kindly use the college predictor app. I hope this will resolve your query.
https://www.shiksha.com/b-tech/resources/jee-mains-college-predictor
All the best.

Yes, they offer marine engineering with good reputation and placements.

Both are good colleges. For mechanical and civil, go for CVRCE.

They are good enough to clear all your difficulties in your academics.