Odoo Online v.12

This is my first forum post. Please go easy on me. If there's an article or something out there that answers any part of this, please feel free simply to point me in the right direction. I have looked, believe me, but maybe I missed it.

I want to use Odoo Studio to add a column to a List View. I have had success doing this in the past, but in this specific case I am apparently helpless.

Specifically, when I click into a particular Vendor Bill, in the Other Information tab I have a field labeled Reference/Description.
This is the field I want to add as a column to the List View for Vendor Bills.

I'm looking at Vendor Bills. I activate Odoo Studio. Because the field for which I want to add a column is an existing field within every vendor bill record, I look for the field name (Reference/Description) under Existing Fields in the Odoo Studio pane. There is no Existing Field with this name. Dammit. I try several similar-sounding names, but none of them gives me a column with the values I want to see when I drag it out of Studio and into the List View.

Terrific. So I guess I'm going to have to create this column myself, which Odoo Studio seems to allow ("New Fields").

At this point I should probably mention that I do not understand the distinctions between One2Many, Many2One, Many2Many, Related Field, etc. Like, I know what the words many, to, and one mean in English, but that doesn't seem to help me here. So already I'm out of my depth. And Odoo does not provide any detailed information (that I've found) on how to use Odoo Studio, or else I would just look that sh*t up myself instead of posting in vain on a public forum like some chump. Anyhow...

So I've determined that I need to add a customized field to get what I want from Studio. I try many permutations, in each of the field types (Many2One, et al.) mentioned above. At some point I realize that these menu trees I'm clicking through to create this field keep looping back around and I'm stuck in an endless loop trying to find SOMETHING that looks like what I want, which again, is a column expressing the field labeled Reference/Description that I see in the Other Information tab on my Vendor Bills. So I'm getting nowhere. Time to try something else, something specific.

I know that when I'm in Developer/Debug mode, I can hover over a field label on a form and get a popup containing some kind of descriptive code. Maybe that's what I need? So I go into debug mode, click into a vendor bill, and hover over the field label. Surely knowing what Odoo calls this field in its code will somehow help me track it down in Odoo Studio so I can add it to a different view, right?

Here's what the popup says:

If this information is useful to me -- I don't think it is, but I've been wrong before -- then I do not know how to make use of it. I want to be able to figure this out myself but I have never dealt with a system so frustratingly opaque. And in what appears to be a targeted effort to make me as angry as humanly possible, Odoo Tech Support has a rule prohibiting them from assisting with any Odoo Studio matters. So here I am, screaming into the void. Help?