What You need:
Functioning windows computer
Samsung drivers https://developer.samsung.com/galaxy...er-for-windows
Step 1: Put Phone In download Mode by holding down Volume Down+Home+Power Buttons.
Step 2: plug phone into computer and make sure odin shows a com symbol with the word com and a number If it doesn't then use the drivers link I provided
Step 3: load ap bl cp and Csc into odin and then click start when it loads completely.
Step 4:wait for phone to complete flashing and it will reboot to recovery do not touch it until it reaches the setup screen
And you are done.
WIFI CALLING, VOLTE AND ATT VIDEO CALL DO NOT WORK ON THIS FIRMWARE ON ATT OR SPRINT(CORRECT ME IF IM WRONG) ALSO THIS WORKS ON ALL US MODEL S7 NOT S7 EDGE