NYC local and VS Au flyer here.
You'll have no problems at all. NYC is very multi cultural, and its basically open 24/7/365. Your vacation days are not the same as other ethnicities/ religions/ beliefs.
As others say: Yellow cab is fine/ best if you are with heavy bags or more people, or unsure where you are going.
Fixed flat fee, plus any tolls (midtown tunnel?) and a tip. 20% is standard everywhere. You can pay by credit card. Do not take offers from unlicensed drivers hanging around the arrivals gate. Uber/ Lyft fine tho. Think around $90-ish total with everything.
Air Train is pretty good, goes in two directions:
1) AirTrain North to Jamaica, where you change to either E subway train, or an overground train into Penn station.
E subway switch is a little bit of a schlepp down long stairs, out of station, along the street 50 yards, then into subway. Overground train is in the upper station and faster.
2) AirTrain South to Howard Beach, then the A express subway train from there, to Manhattan. This is a much easier switch to subway, just down an escalator, tho' A trains are a little less frequent.
I use the Option (2) subway/ AirTrain all the time, even flying Upper, as its so reliable, no traffic delays.
(plus it takes me to my local stop) Only when with Family plus lots of luggage do we take a car service.
AirTrain is a little more expensive than regular subway, (separate tickets) but right now is half price or even free, as they are rebuilding and don't want people driving to the airport. They are pleading with people to use the train, hence the discount/ freebie. Not sure how long that will last, but you know... contractors over-run is pretty normal!
Good luck.