You need to enable VAT in the F11: Features of your company to start using VAT features in Tally.ERP 9.
To enable VAT
1. Go to Gateway of Tally > F11: Features > Statutory & Taxation.
2. Set the option Enable Value Added Tax (VAT)? to Yes.
3. Enable the option Set/alter VAT details?. The Company VAT Details screen appears as shown below:
4. Enter the required details in the VAT Details screen:
5. Press Ctrl+A to accept the Company Operations Alteration screen.