Probably the situation differs on the whole setup of health-care in the nation you live, but as a rule of thump you just pick the one close(st) to your residence, so they can pay house-visits if necessary.
I once had one near my old home, moved, couldn't be bothered to change (I'm hardly ever sick, and it was a good practice anyway), but at some point I had to pay him a visit and he told me I lived to far away for him to make a house-call.
Still took me three years or so before a new practice was set up visually next to me to make the actual change. I simply never had the urge to change.
Sometimes they are 'full' though. Although I think that problem has been solved here.
If there are many in your neighborhood, I guess you could write them if they accept new 'patients', and could ask them on the services they provide, or in case you have specific needs, if they can accommodate you.
Hoped this helped.
And YAY for health insurance

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