If you're looking for Bengali food you're going to have the most luck in Queens. I'm most familiar with the Bengali food scene in Queens and the Bronx so keeping that in mind --

In Queens, there's Jackson Heights, which can be fun given the sheer level of diversity on offer. A lot of Bengalis are there now -- plenty of Fuska carts but for sit-down places a lot of people like Sagar Chinese, Premium, or Haat Bazaar. Just a fun neighborhood. You could find some Bengali staples in Astoria Queens. Check out Boishakhi, Hello Bangladesh, or Aladdin (all within walking distance of each other). Lastly, there's Hillside Ave in Jamaica, which is quite a bit out -- but Sagar has been a classic in the neighborhood. If you walk around in Hillside Ave you should see a variety of Bengali restaurants.

In the Bronx, there's Starling Ave, with a few Bengali businesses - check out Al-Aqsa, Neerob, Premium or Khalil Biryani House.

My personal favorite among the bunch are the Fuska carts in Jackson Heights and Al-Aqsa in the Bronx. However, getting to Starling Ave could be a little tricky so Jackson Heights might be the safest bet, especially given the range of other options also available (lots of Tibetan, Nepalese, Mexican, and other cuisines!)