What does Simon say they should do & how do they react in Chapter 8 of Lord of the Flies?
I think that what you are talking about is the part in Chapter 8 where Simon tells everyone that they need to go climb the mountain. He is saying this in response to the discussion about what to do about the beast and how to react to Jack and the hunters leaving the group.
When he says this, everyone is pretty nervous and scared and unwilling to climb the mountain. They do not want to climb the mountain because they are pretty sure that the beast is up there and they are very afraid of it.