See Write Text Patterns to Column for the basic of using a Text Builder action. These advanced actions allow you to create
Actions
...write URL Pattern and text pattern to link column
Templates
When button clicked...
When status changes to something...
When an items is created...
When item name changes...
When column changes...
Use actions in the custom automation builder to support additional triggers, and trigger conditions!
Supports writing to subitem columns when using the "when column changes" trigger with a subitem column.
Usage
The "URL Pattern" field lets you create the URL that clicking the link field will take you to, and the "text pattern" creates the text that is displayed in the link column of your board.