This article explains how a Tax can be configured for items on your menu.

- Head to Ordering >>Taxes>>click on ADD Tax
Title: Enter the title/name of the tax. (Ideally, this would be GST)

CRM Title(optional field): You can enter a title purely for your reference. Details entered in this field will not reflect on the UI of any platform.

Description(Optional field): You can describe the tax that you are creating. Again, the description will not reflect on the UI of any platform

Active: Enabling or disabling this flag would determine if the tax is applicable or not.

Type: You can either choose Applicable to Fields or Fixed Value. Since the tax is a dynamic amount that is calculated on the price of items added to the cart, you will have to choose Applicable to Fields from the drop-down.

Provided you have chosen Applicable to Fields from the Type drop down, you will see 3 more fields: Fields, Type, and Value.

Field: You will see a bunch of options from the drop-down, but since tax is only applicable on an item price, you can choose Item Price from the list.

Type: Again among the 2 options, since tax is calculated only on a percentage basis, you can choose Percentage from the list.

Value: Here's where you can add the percentage value that will be calculated on the item price. The sum total of tax calculated on every item added on the cart will be added to the order subtotal.

Once done, save!

After saving, you will see a new field on the page: Item and Location Groups

By default, you will see All added as a pair in both Item Group and Location Group Fields which would imply that this Tax is applicable on all items and all locations configured on the portal.
In case you have only a particular set of items or locations on which this tax needs to be applied, you can go ahead create an item group or location group or both (here's a link on how to create groups)Provided the respective groups are already created, you can delete the default pair (which is all items and all locations), add a new pair and select the desired item group and location group where this tax has to be applied.