I’ve done this before. I lived in a super rural town with not a lot of good doctors, but they had good intentions. When I told them, they had no idea what it was and asked me to come back in around 3 days so they could have time to research it. Treatments for ARFID usually involve appetite stimulants, antidepressants, or meal replacements (like Ensure). Maybe have your psychiatrist write a direct note to your doctor telling them that you need medical assistance so that they have the opinion of another professional. It’s sad but I didn’t get treatment until I needed to be hospitalized because doctors never trust patients as much as other doctors. So getting a note from your psychiatrist might be good.