Hello!
Following are the list of colleges:
1. Amrita School of Business - [ASB]
2. PSG Institute of Management - [PSGIM]
3. Karunya School of Management, Karunya University - [KSM]
4. Karunya Institute of Technology and Sciences - [Karunya University]
5. Rathinam Institute of Management - [RIM]
Check out the link below:
https://bschool.careers360.com/colleges/list-of-mba-colleges-in-coimbatore

Here are the top Five business schools of Coimbatore-

PSG Institute of Management, Coimbatore,

Kumaraguru College of technology,

Amrita School of Business, Coimbatore

KCT Business School, Coimbatore

KV Institute of Management and Information Studies, Coimbatore. 

You should choose 

PSG College of management 

It's best in Coimbatore 

Even Amruta school of business is good .

https://bschool.careers360.com/colleges/list-of-mba-colleges-in-coimbatore

PSG is one of the top colleges in Tamil Nadu so try for it .

All the best