Logo Hangs

So one day i decided to update my S6 from 5.0.2 to 5.1.1. I downloaded smart switch and updated through there.
The phone worked perfectly until I realized I need to root my phone so I attempted to root through TWRP using UPDATE-SuperSu 2.46.zip and I got stuck in a boot loop. :(

Then I searched google how to get out of my problem and somewhere along the line, I deleted my OS by deleating System in the wipe section of TWRP.

I tried to flash the stock rom but Odin gives me this error:
<ID:0/004> Odin engine v(ID:3.1100)..
<ID:0/004> File analysis..
<ID:0/004> SetupConnection..
<ID:0/004> Initialzation..
<ID:0/004> Get PIT for mapping..
<ID:0/004> Firmware update start..
<ID:0/004> SingleDownload.
<ID:0/004> sboot.bin
<ID:0/004> NAND Write Start!!
<ID:0/004> FAIL!
<ID:0/004>
<ID:0/004> Complete(Write) operation failed.
<OSM> All threads completed. (succeed 0 / failed 1)

I am at my wit's end here and I really need some help so please reply if you have any useful information to get my phone back to normal.
I'm not sure if this has to do with anything but my phone says:
SW REV. CHECK FAIL. DEVICE: 3. BINARY: 2