Dear student!

You haven't mentioned whether you want to go for UG or PG course. If it is UG, then you get admissions through AIEEA UG, through ICAR exam. 500 is a good marks, but still it depends on your rank and category whether you get admissions in IARI, New Delhi or not.  With 500 marks you have a good chance though.

Hope this helps.

Good luck!