Example of Multi-Option attribute
Create attribute Color&size.
Create Parent Attribute (no values): If you don't already have a parent attribute that will contain your multi-option combinations, you'll need to create one. This parent attribute must be one of the following Element Types: Selectbox, Multiselectbox, Checkbox, or Checkbox group. This parent attribute will essentially group the child attributes/options. Give it a descriptive name (e.g., "Size and Color")
Create Child Attributes: Create the individual global attributes that you want to combine into a multi-option. For example, you might have a "Size" attribute (Selectbox) with values "Small," "Medium," "Large," and a "Color" attribute (Selectbox) with values "Red," "Blue," "Green."
Add Parent Option to Product: go to the product edit page click to add a new Color&Size global attribute to the product
Configure Combinations (if necessary): Depending on your setup, you might need to configure the specific combinations of child attribute values that are allowed in the product. For example, you might only offer "Small - Red," "Medium - Blue," and "Large - Green."
In the storefront product page, the customers can choose a combined option valueThen, when adding the "Size and Color" multi-option to a product, customer can choose the specific combination
