MCA

MBA IT is better career option for MCA graduates because they can easily work in Pre-Sales support ,sales & marketing or business analyst roles in ITES/IT industries. Operations specialization is more suitable for engineering graduates.

Yes, BCA and MCA is a good course if you want your career in IT field. This course will help you in getting a good job and MCA is also equivalent to B.Tech in CSE or IT. This course can be pursued by any student from science or commerce background. Career prospects are also good in this field.

MBA is a better option since you've done BBA. However, if you're not interested in making a career in the management domain, you can opt for MCA degree, provided you have a keen interest in technical field.

You can do MCA after B.Sc agriculture if you had maths as a subject in class 12th board examination.

During your BCA you would have come to know of your technical strengths. If you technically oriented and good in programming then MCA is very good career option. However if you not technically oriented MBA in finance can be a good career switch option.

A software engineer is a person who applies the principles of software engineering to the design, development, maintenance, testing, and evaluation of the software and systems that make computers or anything containing software work. After MCA if you work in the filed of software engineering, you will be known as Software Engineer. Additional courses or certification will help you to grow in your career as a Software Engineer.

You can pursue M.Tech in CSE or IT otherwise do Ph.D in computer application.

To know about SAP, kindly refer to the link mentioned below:
http://www.saponlinetutorials.com/what-is-sap-erp-system-definition/
Yes, you are eligible for pursuing SAP.

Following are the best colleges to pursue MCA:
1. Heritage Institute of Technology (HIT, Kolkata)
2. Guru Nanak Institute of Technology, Kolkata (GNIT, Kolkata)
3. Pailan College of Management and Technology (PCMT)
4. National Institute of Technology, Durgapur (NIT-D)
5. Netaji Subhash Engineering College (NSEC)
6. Techno India College of Technology (TICT)