Follow the below step to create and tag modifiers or addons to any items
The complete step to tag modifiers to any catalog, item, or variant is divided in to 3 phase
Phase 1: Modifier creation
Phase 2: Modifier Group Set creation & tagging to catalog, items, and variants
Phase 2: Modifier Group Set creation
Operation >> Manage Modifiers >> Add Modifier Group Set
Step1: Click on Add Modifier Group Set.

Step2: Enter the Modifier Group Set Name and click Select Modifier Groups.


Step4: Click on the Save button.

Step5: Click Edit Assignment to assign this Modifier Group Set to items.

Step6:Click on Assigned Items tab.

Step7: Select the Catalog Level (Catalog / Item / Variant) where you want to assign the Modifier Group Set.

Step7:Click Update to save the assignment.

Phase 1:Modifier creation
Phase 2: Modifier Group Set creation & tagging to catalog, items, and variants