For this requirement of yours you have to create a vf page with an dependent picklist. This dependent picklist value will display the fields value according to the selected picklist value. In my vf page I am changing the values of the dependent and depending picklist in my controller. So for your requirement you have to create your page and controller somewhat like this in which you have to change the field values depending on dependent picklist.
<----------controller----------->
public class dependcustompicklist {
public String selectcity { get; set; }
public String selectcountry { get; set; }
public list <SelectOption> getcountry()
{
list <SelectOption> opt = new list <SelectOption> ();
opt.add(new SelectOption ('','Select'));
opt.add(new SelectOption ('India','India'));
opt.add(new SelectOption ('US','US'));
opt.add(new SelectOption ('UK','UK'));
return opt;
}
public list <SelectOption> getcity()
{
list <SelectOption> opt1 = new list <SelectOption> ();
if(selectcountry != null)
{
if(selectcountry == 'India')
{
opt1.add(new SelectOption ('','Select'));
opt1.add(new SelectOption ('Kanpur','Kanpur'));
opt1.add(new SelectOption ('Ghaziabad','Ghaziabad'));
opt1.add(new SelectOption ('Noida','Noida'));
}
if(selectcountry == 'US')
{
opt1.add(new SelectOption ('','Select'));
opt1.add(new SelectOption ('Washington DC','Washington DC'));
opt1.add(new SelectOption ('New York','New York'));
opt1.add(new SelectOption ('Los Angeles','Los Angeles'));
}
if(selectcountry == 'UK')
{
opt1.add(new SelectOption ('','Select'));
opt1.add(new SelectOption ('London','London'));
opt1.add(new SelectOption ('Paris','Paris'));
//opt1.add(new SelectOption ('',''));
}
}
return opt1;
}
}
<----------Page-------------->
<apex:page controller="dependcustompicklist">
<apex:form >
<apex:pageBlock >
<apex:pageBlockSection title="Country Name">
<apex:selectList value="{!selectcountry}" label="Country" size="1">
<apex:selectOptions value="{!country}" rendered="true"/>
<apex:actionSupport event="onchange" reRender="cu"/>
</apex:selectList>
</apex:pageBlockSection>
<apex:pageBlockSection title="City Name" id="cu">
<apex:selectList value="{!selectcity}" label="City" size="1" disabled="{!ISNULL(country)}">
<apex:selectOptions value="{!city}" rendered="true"/>
</apex:selectList>
</apex:pageBlockSection>
</apex:pageBlock>
</apex:form>
</apex:page>
Thanks.