It is a simple page here is the code 
<apex:page standardController="Opportunity">
            <apex:outputField value="{! Opportunity.Name}"/>
            <apex:outputField value="{! Opportunity.Amount}"/>
            <apex:outputField value="{! Opportunity.CloseDate}" />
            <apex:outputField value="{! Opportunity.AccountName}" />
</apex:page>
What's wrong