how do you update your nextcloud?
what are the steps?
possible to auto. sync prod with test environment?
kindly
aadursun
open administration panel
then (sorry it is in french) click on
“ouvrir le système de mise à jour”
and then
It might be easier to provide a specific answer if you instead start with answering:
Why do you ask? 
This is because your concerns and motivations will drive the answer because everybody is a bit different.
Additionally, the specifics depend a great deal on how you installed Nextcloud (i.e. Bare metal/Docker/VM/etc.).