I resolved it!
To do this:
1. WooCommerce > Settings> Tax
2. Prices entered with tax: YES
4. Calculate tax based on: Customer billing address
5. Shipping Tax class: Standard
6. Display prices in shop: including tax
7. Display prices during basket and checkout: including tax
Under Standard Rate – I created the 7% GST tax. My mistake was to fill in State Code fields and City Fields. I should have left those blank and just enter the Country Code only.