You must learn to ski in a ski school, with other complete beginners, not by having someone who can ski 'show you the ropes,' IMO.
Unless dp/ friend etc. is VERY experienced, and has taught people before, I wouldn't bother learning off them. They'll typically want to go too fast too soon, and not be up to speed on the step-by-step thinking that needs to happen to get a beginner to stay upright, move, stop, turn. (The 'teacher' will have already incorporated advanced skiing technique into their automatic movements and probably won't be able to break it down into 'words of one syllable,' IYSWIM).
Honestly, you'll love it. Although getting up when you've fallen (which you'll do a lot of in your first few weeks) is knackering for those of us who like too many cream pies.
Oh, and in the afternoons after your classes, I would think at least twice about going out with advanced skiers who'll allegedly 'ski at your pace'. They won't. Meet up with some of your fellow ski buddies for hot choc / leisurely baby slopes / baby oil on hot Italian ski-teacher's hairy chest.