Seeking custom field that can tether a task to a a key resource (link, doc) already added to the project overview

I really want to be able to have a customer field that would help me tie a task to specific resources (links, docs).

I found the Key Resources section in the Overview tab of a Project, but I can’t figure out how to reference a resource in a field in the List tab of that project. It would be INCREDIBLE to be able to have specific, clickable key resources for specific tasks.

I imagine there is a way to do this?