Yes, Vat is applicable on paddy, rice and wheat except the coarse grains.
When your turnover excveeds Rs. 5,00,000/- in any given FY then you are liable to apply for registration.
You have to fill Form VAT 100 for the registration of VAT.
Below is the link from where you can get the form.
https://www.apct.gov.in/allacts/vat/forms1/VAT%20100.pdf |