You can take either public transportation or uber/cab. If it is during rush hour it can take up to an hour or more. Otherwise up to 45 min.
We just left NYC and used Google maps to navigate the air train, subway, and buses to get around Manhattan. It really wasn't difficult because everything is color coded and numbered, and people were really helpful if we were unsure what platform side we were supposed to be on.
Glad someone knows, I was just on a international connecting flight, never left the airport nor did I want to
Either take a Taxi/Uber/Lyft for about $75 or the Subway for $20 (JFK Terminal 4 to Jamaica Station> Pennsylvania > 50 St Broadway) either way it's going to be about an hour and 15 minutes, unless it's early morning then maybe 30 minute ride
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