How to set date & time to New York Time

Only broker on server side can adjust time zone. You cannot change time zone using client terminal.

compare the different between server time and NY time in hour(s) then

get the curtime() function , this result in seconds

add the curtime() with the different hour(s) in seconds

ie. server time is gmt+1 and you are in gmt+4 then
the different between you and server is 3 hours or 3*60*60 seconds
then your time is curtime()+(3*60*60)