Ime turning windows laptops off is really hard. You tell them to shutdown and they restart for some reason, and it does not seem to be update related because it happens with laptops completely offline too. So you may think that you have shut them down, close the lid, but actually they reboot and when you get to them again they are dead. This happens with some dell laptops but I do not think it is just them. Not all the time but very randomly.
I haven't found a way to tell Windows 10 to hibernate other than making that the power button action in power options. Maybe because it's a laptop but it starts immediately after hibernating and your have to hold the power button to fully turn it off. This works and skips any forced updates Windows wants to do. It is very janky and I think ms does it to make skipping updates harder.
Apparently "update and shutdown does a restart instead" was very recently finally fixed: https://news.ycombinator.com/item?id=45797934
To shut Windows down, press Win+R to see the Run dialog and then type shutdown /s /t 0