Under certain circumstances with Samsung phones you can go back to a previous version, without tripping knox, but this does result in a total phone wipe. But for all intents if will still be all genuine.
And this is only if the current software your wanting to revert from is not a generational leap away from the version you actually want to go back to. This will be down to a bootloader version if I remember rightly. My gut feeling is that if you've updated from Android 13 to the new version 14, then your out of luck. If it was an incremental update that was still within the current OS version then you may be in luck.
It's been a while since I faffed around doing this with a Samsung phone, so you would definitely want to get some up to date advice from XDA.
Mick