Most such jobs require service as a ground pounder before application to air ops. In many cases air ops is clicky, and hard to get into since it's not too hard to get a CPL.

Depends on the department, IIRC some even hire pilots off the street. In that case you might go straight to air or maybe serve some ground time first so you know what you're supporting.

You'd really need to get some HUMINT from the department in question.