You can write a good thesis.
You can make yourself prepared for your viva.
You can know what to expect from your examiners.
You can know what to expect from the viva.
You can learn about remote vivas, if that’s likely to be the scenario for your viva.
You can build your confidence to balance out your worries.
You can’t be perfect, but you can do your best.
You can be good enough for your viva.