How to Link a Modifier Group to a Menu Item
Once a modifier group has been created and populated with options, it must be linked to the relevant menu item(s). There are two ways to do this.
Option 1 — Via the Modifiers section:
Navigate to Your Menu → Modifiers
Locate the modifier group and click Edit
Click the Linked Menu Items tab
Click Add Menu Item(s) to Group
In the panel that appears, click the Select an option field
Scroll or type to search for the menu item(s) you wish to link. Multiple items can be selected at once.
Click Submit
Option 2 — Via the Menu Item:
Navigate to Your Menu → Menu Management
Click on the Menu Name the item belongs to
Locate the item within its category and click Edit
Click on the Modifiers field
Type the modifier group name or scroll to find it, then click to select it
Click Save Changes