girlfriends learning to drive just now and her instructor told her that i can take her out showin L plates as long as its in a car park etc

does anyone know the legalities of me takin her for some lessons?
does it have to be in private car parks or industrial est etc? or can i take her out in the open road?im i insured or does she need to be added to my insurance,all a bit confusing for me
any help appreciated