I have been an Alpine skier for over 40 years, but in recent times I have added some Nordic backcountry skiing to my agenda – the main reason being that I can do it in my home area whenever it chances to snow (rarely). I just take a bus up to the local hills and ski my way home, mostly downwards. Failing that, there are modest mountains close by that offer snow more regularly and within a hour’s drive from my home.
To take advantage of Nordic backcountry skis, you don’t really need to learn Nordic downhill techniques (telemark). If your skis are short, soft and shaped enough, you can persuade them to do Alpine turns – though you do need to learn a few cross-country elements for the gliding (flat) and uphill portions of your route.
That said, here is the first page of a good primer from Australia (of all places). The text is somewhat concise, but gives you a brief overview of the skills to learn, upon which you can base further research on the internet.