@Rafael, OK, I understand now...
When you create a new type of entity, in the settings of this new type, you have "List item settings" -> "Entity class" and here you can choose between three options:
- Individual person
- Organization
- Individual person without aditionnal forenames

If you choose the #1, your new entity type will display all fields: Prefix, Forename, Middle Name, Surname/organization, Suffix, Other forenames, Display name
If you choose the #2, your new entity type will display only Name and Suffix
If you choose the #3, your new entity type will display same as #1 except Other forenames.
So, in you case, I understand that you should choose #2 option.