Sprint review question

Is the "sprint review" done after or before we release in Production environment the new features?

Which approach would best help the team to understand the work that has been Done and remains to be Done, and to update the Product Backlog accordingly?

The Sprint Review should never be considered a gate to releasing value.

I would suggest decoupling the concepts of "Sprint", "Sprint Review", and "release to Production environment".

A Sprint is, in my opinion, best viewed as a planning horizon. Two of the most important factors in determining the Sprint length is how far out the team can create a stable plan and how stable the environment being supported by the product is. These tend to be related - more instability in the environment means the team can't plan as far out, which should tend toward shorter Sprints.

The Sprint Review is the next-to-last event in the Sprint and is primarily a point of synchronization between the Scrum Team and key external stakeholders. This doesn't mean that it's the only time that the team can synchronize with stakeholders, but it provides a regular cadence for everyone to come together and assess where things are and what the next best steps are.

Work can be released to Production at any point. Maybe you practice Continuous Deployment and deploy every Product Backlog Item as it reaches Done. Maybe you deploy once a day. Maybe you deploy every few days. Maybe you deploy once a Sprint. Maybe you deploy once every couple of Sprints. Since the Sprint is a planning horizon and synchronization cadence, it has little to do with deployment frequency.

The team's Definition of Done may also be considered. The Scrum Guide states that Product Backlog Items that do not conform to the Definition of Done may not be "released or even presented at the Sprint Review". Strictly speaking, if "deployed to production" is part of your Definition of Done, then you should deploy the work to Production and only consider these Done items during the Sprint Review. However, the Definition of Done tends to be within the control of the team or teams working on the product and can be discussed and changed at the Sprint Retrospective if the current state isn't working well for the team.

@Thomas Owens  Many Thanks for the answer. Really appreciated and helpful!