There are many different questions someone might have about cross country skiing. My advice: rent first, go to a touring center with good grooming, and take at least one lesson. I know from experience how hard it is to self-learn the sport.

But if you do it the bootstrap way, here’s a few links to get you started:

Technique intro videos

Literally getting started:
Getting Started in Cross Country Skiing

Description of classic and skate technique:
Essential Intro to Cross Country Skiing

Basic body positioning- flexed ankles and knees, rounded shoulders, center of gravity pushed forward:
Forward Body Lean in Cross-country Skiing

An expert instructor showing how to stop:
How to stop on Cross Country Skis

Yes, they’re all Canadian. Three of four were done at Canmore Nordic Centre Provincial Park, and the other at Silver Star-Sovereign Lakes.

The “Here’s what I learned” approach

This blog posting gives some pointers, including a bit on the inevitability of falling, in a comforting and casual tone: Embrace the Wobble and Six Other Lessons I Learned As a Novice Cross-country Skier

RTFM / TL;DR

This next link has a pretty comprehensive (maybe TMI) menu of skills and techniques to know about the sport: Beginner’s survival guide to cross-country skiing (the author’s title, not mine). Probably better as a reference guide for novices than an instructional manual for newbies.