NEET AND ICAR Have similar syllabus topics if you choose PHYSICS,CHENISTRY AND BIOLOGY.

The time limit and level of difficulty of questions changes.

ICAR EXAM PAPER PATTERN AND SUBJECTS: 

The exam paper will contain the questions from these subjects - Physics, Chemistry, Biology, Mathematics, and Agriculture. Depending on the chosen stream, aspirants will be asked questions from three subjects maximum.

So, it depends on what subjects you choose to write.