Examiners sometimes ask a candidate to prepare a short presentation to open the viva. They’re always clear about whether or not this is something they want: regulations might mention them, your department might have them often, but your examiners will be specific about whether or not they want one, and if they do, help set some expectations for what you could do.
“Ten to fifteen minutes summarising your thesis.”
“A short overview of each of your chapters and their key points.”
If your examiners ask for a presentation then prepare one in a style that works for you. Break your work down as best you can. Practise doing it so that you know you’ve got your points covered in the time you have, then go and start your viva in a good way.
If your examiners don’t ask for a presentation, there could still be a lot of value in preparing for one.
Summarise your work, connect ideas clearly and concisely, then practise delivering it with an audience of friends who can ask you questions and offer thoughts. There may be a little more work involved with this than with a lot of general viva prep ideas, but it can be a really useful way to help convince yourself you’re ready for your viva.