"Coach" is not a regulated title and there is no specific education.
So it depends on what this "coach" actually has in terms of skills on offer. You kind of need to know what you need to work on in order to know if a given coach can help you with it.
What kind of clients do they normally work with? What kind of results do they normally get? What is their fee? What is their area of expertise?
I used to do some career coaching in my industry and I had a colleague who was also a very effective career coach in the exact same health profession, and yet we did completely different things.
I helped people figure out their best career trajectory, helped them network their way towards it, and worked with them on building their professional identity and goals.
She helped more established professionals make more money. That was her main goal, and she was very effective at it and had clear plans and timelines for getting people there.
I just vaguely promised that I would make them happier with their career. But I had such solid professional reputation for doing this that people who needed help just found me.
She would have been useless for someone who needed me, and I was pretty good at helping people make more money, but nowhere near as systematic and effective as she was.
So as I said, you need to know what you need in order to even be able to assess any given coach's value to you.