There are resources online to find well-reviewed instructors, but I agree with earlier comments that the real key to learning is clear and effective communication from the instructor in a way that you can easily “get”.
I’ve been taking a series of lessons at a GolfTec center not too far from my house; started with a free evaluation they’d offered as a bonus for donating to a veteran’s charity (which I do anyway).
That seemed to go well so I signed up for one of their “Lesson Packs”. I was making some progress, tho as it turns out that instructor retired.
Got paired with a new coach … really nice, young guy … who’s very patient and has no problem telling me, showing me, telling me again, then showing me again in a different way every thing we work on until it starts to sink in.
And I’ve definitely been making good improvement!!