connect a field to a new custom taxonomy

I have a site that uses Pods and I have already loaded all of my custom posts and data. I am making use of Categories and Tags, and I’d like to create a new custom taxonomy and associate it with one of my existing fields in my Pod. Is this possible? I created a new custom taxonomy type and assigned it to my custom post type, but it’s just a blank field that I would need to populate. I have too many items to do that manually. Is there any way to make use of my existing data in a custom field for this new taxonomy? Any help is appreciated.