is this real? Yes, dont believe it then don't get it.
is online supported? No they are currently no servers online and there never will be.
does it crash on start? No and if it does let me know.
is it a virus that will affect mt device? No, don't believe it then don't get it.
can i add other mods?, if so how? Yes you can but there are little to no mods. Applying mods should not be complicated but I do not know how to.
NOTE: THE REAL FRIDAY THE 13TH GAME HAS NOTHING TO DO WITH THE SERVERS OF THIS GAME. THIS GAME JUST SIMPLY HAS NO SERVERS ONLINE AND THERE NEVER WILL BE ANY SERVERS ONLINE.