[Plugin: WP Job Manager Field Editor] Adding new dynamic dropdown field

Hello,

I am using Listify theme and I need to add new fields on the Submit Listing Form. The problem is I want it to be dynamic. What I need is a locations dropdown with a text box for a number next to it. This is for the installer to provide the number of installations done in any given location. Would that be possible without any major code changes using only Field Editor Plugin?

I am not a WordPress expert, just know some basic html, css, php. Would appreciate any help. Thank you in advance!