I Believe I Have Adult ADHD. Family Members Have Suggested

I believe I have adult ADHD. Family members have suggested I see a doctor as well as my therapist suggested I see someone. I am nervous to begin a conversation like that with a doctor in fear they will think I am just trying to get drugs. How do I approach this situation? Also, I don't have a primary care physician and don't know if it's appropriate to meet them for the first time and ask for a prescription. Is that normal?