M.Sc

JAM is for M.Sc. You can take JAM, only after graduation. For integrated B.Sc, you will have to appear for JEE.

B.Sc with Zoology/Fisheries/Fishery Science/Aquaculture/Industrial Fish and Fisheries as one of the subjects in three subjects of equal importance/B.Sc., Degree in Fisheries or B.F.Sc are the most preferable branches for M.Sc. Aquaculture.

Basic eligibility criteria for this course is that applicant should have completed graduation from a recognized university. Since you have completed your graduation in B.Sc Maths, you are eligible to pursue a course in M.Sc IT from Sikkim Manipal University, Directorate of Distance Education. Moreover, you will be given preference over other candidates as you have a B.Sc degree.
Admission Process:
Register and Apply
Interested candidates can apply online with the required information.
Merit Screening
Admission is based on the marks obtained in graduation.

Yes, you are eligible for M.Sc, but please check eligibility criteria for the institution/University, because different universities have different eligibility criteria.