Create your combo box with ID, LastName, FirstName and PhoneNo. In the After Update event of the combo box use code like this:
Me.LastName = Me.ComboboxName.Column(1)
Me.FirstName = Me.ComboboxName.Colmny(2)
Me.PhoneNo = Me.Comboboxname.Column(3)
Change the names to reflect the actual field names on your form. Remember that the combo box is 0 based so the first column is column(0)