I'm trying to figure out how to get a search result in Google with multiple subcategories for my Shopify store when someone specifically searches for my unique brand or shop name.
Like if you search 'Walmart' you get a result with a search box for the Walmart website, and 6 category header links underneath.
Any advice would be very welcome.
This is a kind of structured data. You can check more details about it on official google forum - https://developers.google.com/search/docs/data-types/sitelinks-searchbox.
Here is a guid on how to implement it on shopify - https://gist.github.com/freakdesign/5d81d97639b5b739f12e