What ID is needed when querying the API for column values?

What ID is needed here? I’m trying to get the values within a certain column. I added the question marks after I ran the query to keep my board ID private. I also tried the column ID. That was rejected for having a non-string, non-integer value in it. I’m finding the API reference pretty useful, but I’m stumped here.

with items, it’s asking for an item ID. unfortunately, that just narrows it down to the column values for that specific item.