One way to ensure a team is holding successful iteration reviews and demos is to have the team demo working, tested system components that meet the definition of done (DoD). This shows the team's progress and value delivery, and allows them to receive feedback from the product owner and other stakeholders. The team should minimize the use of slides and the preparation time for the demos, and focus on the solution instead of the presentation. The team should also discuss the impact of the current solution on the nonfunctional requirements (NFRs) and identify any risks or impediments.
Reference:
Iteration Review - Scaled Agile Framework
Exam Study Guide: SSM (6.0) - SAFe® Scrum Master

One of the best practices Scrum Masters/Team Coaches can use to run successful meetings is to leave meetings with clear action items. Action items are specific tasks that need to be done by a certain person or group by a certain deadline. They help the team to follow up on the outcomes of the meeting, track progress, and ensure accountability. Action items should be SMART: Specific, Measurable, Achievable, Relevant, and Time-bound. Scrum Masters/Team Coaches should document and communicate the action items to the team and stakeholders, and review them in the next meeting. (Must be taken from SAFe 6 Scrum Master resources) Reference:
Scrum Master/Team Coach
How To Run Effective Scrum Meetings - Xebia
Four agile ceremonies, demystified | Atlassian