Answer

Under review
Could you provide a more detailed description of what you need please? So far it is not clear where to add the link and what should it do?

Answer
Answered
There is a built-in template called "Metadata" that lets you select a node and display its metadata nearby on the page. You can clone and modify that to open a web page instead. Have a look here for more details on metadata: https://boxshot.com/koru/tutorials/tips/metadata/

We have this in plans for one of the next update, but so far the metadata approach is the only way.
It would be nice if you can point to the implementation you want to match.
Customer support service by UserEcho
There is a built-in template called "Metadata" that lets you select a node and display its metadata nearby on the page. You can clone and modify that to open a web page instead. Have a look here for more details on metadata: https://boxshot.com/koru/tutorials/tips/metadata/