Hello babul good to see you ask questions like this.
All 3 campuses have good CSE faculty, same placements, and comparable facilities.
If you are a person who is concerned about being academically brilliant, getting a very high package job, and enjoy a lush green 500-acre campus, go ahead with Coimbatore.
Bi0s -Bi0s is a cybersecurity club, and the people in this club know to Hack! They play CTF (which is a pretty big deal for ethical hackers) and are consistently rankedIndias No.1 CTFTeam. They also host the annual national CTF -INCTFhere at the Amritapuri campus. They are closely supported by the experts here at Amrita Centre of Cyber Security and connected to a large number of experts across the world. So, if you are interested in Hacking and Cyber Security, I guess there is no better opportunity in India.
FOSS@Amrita -FOSS@Amrita is an active computer science club focused on the principle of FOSS (Open Source), and they explore several fields in computer science (Android, Web, ML, you name it). The students here participate in hackathons around the world, join summer schools abroad, attend and host developer conferences, etc. Thats not all, many of them get paid internships and research opportunities and the FAMOUS of all - the GOOGLE SUMMER OF CODE! Its a program run by Google which pays you 3000USD to contribute to Open Source under projects of prestigious organizations like Python Foundation, GNU, KDE, VideoLan etc.
Code@Amrita- Competitive programming club. If you are into programming, the seniors here will make you the best. Competitive Programming comes in round 1 of almost all interviews, so you know how important it is for you.
In the end the choice is yours hope you got your answer.Thank you

Hi aspirant
Thanks for asking your query, amrita University is good for cse because it has good facilities and faculties, proper classes and lab are there.I suggest you to take admission in the main campus because it is well quiped with all the facilities.
Best of luck