How to stop a game from auto updating on Steam?

Pretty new to Steam overall.
I was just playing Skyrim with some mods, exited the game in order to download/install another mod and apparently the game updated as I was playing....causing SKSE to be out of date. Meaning now I can't play at all until that gets updated.
The only settings I can find basically amount to "auto update is always on, fuck you".

it's on or off for all games. but you can disable updating when playing a game

I'm pretty sure my steam waits until I confirm it.

Unplug Ethernet cable.

If anyone else has problems running modded Skyrim due to the update and doesn't want to wait for SKSE to update I found the fix courtesy of some clever Reddit users.

https://www.reddit.com/r/skyrimmods/comments/xetnls/skyrim_updated_to_16629/