Do you get a discount when you use that N.Y. IS card

If your talking about the nycID card, the New York Aquarium is free however enrollment is only available at the Bronx Zoo.

UPDATE: You can now enroll for a WCS Membership using your NYC ID at the New York Aquarium. You don't have to go to The Bronx Zoo for enrollment anymore.

Yes

I need to make an appointment My husband and I are vaccinated. Hear it is free for those who have been vaccinated