How to adapt/change the local address book template

I have a new Yealink T48G where I want to import all our private phone contact using the CSV import. Since it is a private use I want to change the phone book template to be able to assing "private", "mobile", "Business" and to import my phone numbers in there.
Per default the template shows "Office number", "mobile", "other number". Is there a way to adapt the template to cover my needs.
Thx for any hint