During the preparation time before each role-play in the Speaking test you can ask the interlocutor questions about the task. There is no impact on your result from asking questions and having the answer may even help you achieve a better score. Asking questions will give you clearer understanding which will make you feel more confident.
Things you can ask include:
How do you pronounce this word? [point at the unfamiliar word on the role card]
What does ‘concussion’ mean? [concussion is an example]
What name shall I call you in the role-play?