Google earth measures it at 33.5 miles from exiting Marina Del Rey, CA harbor to the closest point of Catalina Island,CA. But it looks like it is another 15 miles SE to Avalon, where it seems the...
Departure point: Toronto, OntarioDestination point: Long Island, New YorkEstimated flight duration: 1 hour, 17 minutes
4-6 hours give or take and if you go by ferry usually 4 driving it took me 5 hrs once
Fire Island is part of Long Island. It woudl be more helpful to ask how long it takes to get to Fire Island from a particular Long Island town.
That depends on where you're coming from, which you have not mentioned.