Do you have any good friends from high school or any relatives you can stay with for a few days while you sort things out? Where your stay physically comes first. Once that is settled, look to see if you can find a part time job for the rest of the school yr/until you leave for school.
In addition to the resources mentioned above, another thing you need to talk to your GC about – you have a full tuition scholarship to school in August/September. However if your parents are cutting all ties legally, that means room and board and transportation to school are up to you. You should call (or likely have your GC call – bc you have way too much to do right now) your school’s financial aid office and explain the situation; it is likely that with zero parental support and as an emancipated 18 yr old – you will qualify for aid to cover your R&B and at least some expenses. But it won’t happen instantly and the school will likely need some paper work that your GC should help with.
You have to find a way to stick out the next 2 months in NYC, but after that – assuming your in state school is someplace outside the city – it may make sense to head up to college right after graduation. You may be able to find retail/restaurant etc. work in your school city and get a cheap sublet from a student who is away for the summer; frankly if your school knows your situation, they may be able to hook you up with a few employers who are looking. I’m just thinking that it is easier to support yourself on a retail job outside of NYC bc everything is cheaper; whereas if you stay in NYC, you may just not be able to make enough money and will have to rely on shelters or friends who can take you in.