[Help] I cant flash rom in odin

Help guys i'm i a real pinch,

im stuck on firmware upgrade error at startup and can only access download mode.
so i thought i should flash stock firmware following the steps in a thread by someone

but whenever i try to flash stock firmware via odin it gets stuck at Kernel part saying
NAND write start

i searched everywhere and come across the super brick but it is very complicated and i am a newbie.
and i cant really tell the difference between a soft brick and hard brick.

Any help would be appreciated. Thanks