hi,

b.sc honors degree course is three years duration. there is various stream in which you can do b.sc honors like chemistry, physicsm mathematics, zoology, botany, computer science,  agriculture etc. b.sc honors syllabus has more curriculum on the core domain. where general b.sc course has simplified curriculum. so the difference between honors and general b.sc is  honors syllabus is more theory, concepts, chapters included for the major discipline.

now coming to b.sc in agriculture course, this is also three years  duration course. syllabus includes biotechnology, plant chemistry, modern technique for agriculture, fertilization etc. eligibility criteria to apply for b,sc in agriculture is candidates must completed the 10+2 course with physics, chemistry and biology as a mandatory subject. you should apply for ICAR AIEEA ug exam to get admission in undergraduate agriculture related course. apart from ICAR ug there is bhu uet, apeamcet or any other state wise entrance exam.