Hi,
to do this you need to hide all field available into fieldgroup.

Example:
- Group 1: Details
- - Radio Field
- Group 2: Company
- - Field A
- - Field B
- Group 3: Individual
- - Field C
- - Field D

You have these options on radio field:
company|Company
individual|Individual

Set these condition on radio field:
- Condition 1: if equal to custom value "company" show Field A and Field B
- Condition 1: if equal to custom value "individual" show Field C and Field D

Condition have two ways so if condition is not met these hide fields instead show.

Results:

Radio field empty
- Condition 1: hide Field A and Field B
- Condition 2: hide Field C and Field D
so "Company" and "Individual" tabs are hidden

Radio field equal to "company"
- Condition 1: show Field A and Field B
- Condition 2: hide Field C and Field D
so "Company" tab is shown and "Individual" tabs is hidden

Radio field equal to "individual"
- Condition 1: show Field A and Field B
- Condition 2: hide Field C and Field D
so "Individual" tab is shown and "Company" tabs is hidden

How to hide all fields available into fieldgroup?

Hi,
you need to hide all fields that are in that fieldgroup.

Yes, but what I have to do to hide these fields? I don't know how to do.

Ah ok,
documentation sucks and we're working on

For each condition you can set "Target Fields" and "Target Action", target action is applied on all target fields.

So in your case you will need to set these parameters on your radio fields
Condition 1
Condition: equal
Field to compare: Custom Value
Custom Value: company
Target Fields: Field A and Field B
Target Action: show

Condition 2
Condition: equal
Field to compare: Custom Value
Custom Value: individual
Target Fields: Field C and Field D
Target Action: show