Is there a parking garage at the museum or close to it?

There's probably a garage within a few blocks of the museum but there is not one thats affiliated with the museum itself. Parking is not cheap in manhattan.

You should just take the bus or train. $5.50 each adult round trip. Little kids you don't to pay for on public transportation. If you coming from Queens, Brooklyn ect. You can drive into Manhattan find parking garage or a parking spot on the street. Then take the bus or train depending on how far away you are from the museum. I usually park near Manhattan because it's always so much traffic in Manhattan. Then get on the train. It's faster than driving in Manhattan.

None at the museum

We walked from Lincoln center area, a few blocks

Subway or bus is definitely cheaper

No. Take the train.

I don't think so. I would recommend Uber🚗, the Subway🚊, or taking a bus🚌