How can I put external data options into the content-types-builder?


When I try to add a new content entry for some collection, I am able to select some fields of content from the external data. I need to fetch some external data from another database and put the related field into those data. While the editor creating new content, for example, they add name, title, desc and etc, but for 2 fields they must be selected from the dropdown(external data). How can I achieve that?

Thanks in advance