Yes

It’s outside of the Grand Central Oyster Bar & xRestaurant. The 4 corners can be used to whisper back and forth. Walk down to lower concourse level towards the food court.

The FC is easy, because its down Stars. GO to the main Hall and take the stairs on either side.

There are two levels: The upper level & The lower level

No.

Usually NO. But it depends on how bad the weather is ...

I don't think so

You need to take the Train to Stamford, 2 stops until MT Vernon East. You should see it in the Station's information screens

Yes u can, take the 7