Yes you are eligible for NIMCET as you are doing BCA in undergraduate degree. Besides this you must have completed your Bachelor of Computer Application of (3 years duration) from a recognised University and you must have scored at least 60% marks in the aggregate of Bachelor of Computer applications examinations.

If you belong to any reserved category such as scheduled caste or Scheduled tribe then you are required to score at least 55% marks in the aggregate of Bachelor of Computer Application examination.

Read more about NIMCET:

https://www.google.com/url?sa=t&source=web&rct=j&url=https://it.careers360.com/exams/nimcet/amp&ved=2ahUKEwi66e3W2Jj2AhX0X3wKHYWMA8IQFnoECAQQAQ&usg=AOvVaw0fnNod1k89Bwfb2bfOgHP5

Hello,

To be eligible to NIMCET you must have passed three year B.Sc. / B.Sc. (Hons) / BCA / BIT from a recognized University with Mathematics/ Statistics as one of the subjects or B.E./ B.Tech. from a recognized University. If you belong to General or OBC category then you must score minimum 60% marks or 6.5 CGPA on a 10-point scale. If you belong to SC/ST/PWD then  you must score minimum 55% marks or 6.0 CGPA on a 10-point scale. You are eligible to apply for NIMCET Entrance Examination even if you haven't studied Mathematics in 10+2 level. However, you must have studied Mathematics/ Statistics as one of the subjects in BCA to be eligible. To check the eligibility criteria and other details click on the link below

https://it.careers360.com/articles/nimcet-eligibility-criteria