This whole year has felt outside of my control. I imagine, at least at times, that you’ve felt similar.
Still, I could choose how I would act. I could choose how I would approach things. The outcome of a situation might not have been within my power to control, and in some cases I’ve only had a few options to choose from – but I could still choose.
All through your PhD, you’ve made choices. Decisions about methods, choices about projects to follow (or not); you choose which literature to read and follow, and which you will leave out of your bibliography.
During your prep you can choose what actions you take. What steps you will follow to get ready. When you take them and how you do them is up to you.
And in the viva you can choose how you will approach the discussion. How will you listen? How will you respond?
The more actions you take, and the more you act to follow your intentions, the more likely you are to find the successful outcome you’re looking for.