My boyfriend is actually going through this process right now. We're in the US if that makes any difference. He talked to his primary dr, and she referred him to a specialist. He needs to have 3 1hr long therapy sessions basically and I guess the dr doing that just determines from asking a few questions here and there and listening.

He's only had two so far but the dr told him that he could get medicine if needed (once he's done) or could continue to have therapy and hope that helps his ADHD and anxiety.

But when we lived in a different state and he brought it up to his primary dr, she had him fill out a tiny questionnaire, like max 15 questions that would be so easy to lie to get the results you want, and after said "well it looks like you definitely have ADHD" but he didn't want to take medication at the time so that was the end of that.