If your S7 encounters a problem during an OTA (over-the-air) update and got stuck in boot loop, you can, revert it to its previous operating system version, provided you know the exact firmware build.

Problem 1: Galaxy S8 Plus got stuck in boot loop, Android won’t boot up I just recently purchased Samsung Galaxy S8 Plus 2 weeks ago.

How to Fix a Boot Loop in Android. When your Android's system files stop communicating correctly, the device may end up having difficulty starting. Boot loops are the result of system files not ...