Product Option Block: Gift Message
The Gift Message Product Option Block allows the storefront customer the ability to add a gift message on a product page. This will then be passed through to the Shopify Order as a Line Item property, displaying like this in the Order screen:

The Gift Message Block allows for configuration options such as hiding the message fields under a hide / reveal, choosing which of the To / From / Message fields to display, as well as setting character limits and making the fields mandatory.
Here is a quick video that shows how to configure this:
In the most common use-case here is how it will look when displaying on a storefront:

Can't find the answer in our documentation?
Contact Support Introduction to Product Options
Build a Product Options Set
Dynamic Display Logic in Product Options
Product Option Block: Upsells
Product Option Block: Gift Message
Product Option Block: Datepicker
Product Option Block: File Upload
Product Option Block: Inputs (Text, Number, Email, Phone, Textarea)
Product Option Block: Selections (Checkbox, Radio Button, Dropdown, Color Picker)
Product Option Block: Color Swatch
Product Option Block: Image Gallery
Styling you Product Options Image Row Upsell Components