New York City isn't what it used to be like. That was only in the 80s and 90s, nowadays it depends on the location. I currently lived in the West part of the Br0nx for 22 years, just a 10 minute walk away from the train that takes me to Manhattan which is just 20 minutes away.
I also live a 10 minute walk away from the USPS post office and 5 minute walk away from the 24 hour laundrymat and grocery store. Everything is nearby, even the big shopping area which is a 20 minute walk away, where you have clothing/sneaker stores, T Mobile, Sprint, Verizon, Target, Sears, Walgreens, Ballys Gym and Best Buy.
Places I don't recommend is, South side Bronx, Queens, Brooklyn as well as many other parts of Queens and Brooklyn which are very known for drug dealers and high crime.
It also depends on what your budget is on a monthly basis because the rent here is expensive. I live by myself and I pay about $900 for a small 2 bedroom, 1 small closet, 1 kitchen, and 1 bathroom apartment(excluding cable/phone/internet and electric bill) and the area is decent. I can always go out at night 2 or 3am in the morning to go to the Kentucky Fried Chicken spot, or even Manhattan. I've done it before and never had any problems or faced danger. You can choose to live a 1 bedroom apartment by yourself for a little less than what I pay.
I doubt you will ever even have any problems, being 6'5 when most people is 5'4, 5'5, 5'6and 5'7 which is the average height for people living in NYC. The only thing you need to worry about is the living costs and what you can afford, otherwise don't expect too much from NYC since it is one of the most popular and most expensive cities to live in the world.
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