You don’t get to choose your examiners.
You might be able to offer suggestions and discuss who they could be, but you don’t get to choose the best examiners for you; you can’t veto anyone that you don’t want either!
If your supervisor has a firm idea on who would be good then talk it through with them. Listen to their reasoning to feel confident about who they nominate.
You don’t choose your examiners – but as you prepare for your viva they won’t be total unknowns either. There will be lots you can learn so you feel good about the people you’ll be talking to on your viva day.