Usually your insurance web portal will have a search feature for providers and tell you if they're in-network. I would guess there could be third party ones too. I remember seeing info like location, ratings, reviews, and certifications.
It should not be very challenging.
So for now its a personal relationship: what works for one person won't necessarily work for another. Unless you have a twin or clone who can recommend a GP, you simply must do the search.
Sometimes you can ask friends or family who they like, or who they think are good. Sometimes you roll the dice and try someone who seems appealing. If the first visit makes you uncertain or uncomfortable, do not go back -- find another. (I've got this story about a dentist who conducted dental torture on me once...)
Sometimes medical insurance dictates that you choose from a list. Choose a doctor close to home, give them a shot, and change if you don't feel like they can/will provide you with good care.
A good doctor can explain things. A good doctor can discuss uncertainties. A good doctor is always learning, and always willing to research new topics. A good doctor is willing to refer you to someone else (or an expert) and admit when they just don't know the answer.
Unfortunately, a good doctor is rare.