The car won't start!!..

[lkh5650]

Hey guys
I just bought 2010 370z yesterday that is nissan cpo
I just got in my car trying to get to home depot so I can buy a rubber insulating tape to cut the brown wire for steering lock fix.
But I think it's either my car just had steering lock failure or my car battery is dead.
I am not sure which one.
Last night the battery was at 12V.

When I got in my car I pressed down on my brake and it felt stiff... and I pressed down clutch and the car started rolling down as it was on slight downhill parking lot which I thought was weird why isn't brake working. Anyway I pressed start button and it made a couple of attempts but it wouldnt. Now if I get in a car the lock button would just come up in red. No other things..and when I step on clutch and press start nothing happen just lock button lights up again. The car door won't lock either.
Will simple jump get my car going?