How to pass params to CircleCI Job via Approve modal

Hi, I need to pass some params to a job when approving it. For example I have two repos with backend and frontend. When I deploy frontend I need to tell the job what exact branch from backend I want to see in final build.

I think something like that, I can specify a param which values are taken from curl . I return the list of available branches and they are shown as a dropdown below build_approval . User selects value from dropdown and this values is passed to the job. Also I can do pretty much the same for backend repo, in backend repo when user clicks approve I can provide the list of NPM packages from my frontend, so users will be able to specify which frontend they want to see with this backend.