There are no BCA Courses at IITs. The nearest you get is a BSc Data Science Online Program from IIT Madras, started recently.

For more information about BCA and Colleges do follow the link below

https://www.careers360.com/courses/bca-bachelor-of-computer-applications/amp

However, there are many Good Public and Private Universities, you may pursue your BCA or BSc in Computer Science from, followed by MCA from some of the Good NITs by aceing the NIMCET Examination. MCA from NITs are a really good option, provided youre interested in a Career in the IT/Software/Services Sector.

For more information about NIMCET Exam do follow the link below

https://it.careers360.com/exams/nimcet/amp