You buy a pattern, it's yours to use. The quilts you personally make from it are yours to keep, give away or sell. Make one, make a bunch. Make them in whatever color, pattern, size you want. You can use the pattern as a jumping off point and modify it to your personal creative taste.
What you can't do is copy and give away or re-sell that pattern. Unless it's in the public domain.
Making patterns is hard work. You come up with a design, make a dozen to make sure your directions are correct, design a cover, photograph your quilt, buy a barcode, get it printed, try to market them, build a website, do shows, learn social media. Think about that before you ask your friend for a copy of the pattern they just bought. Is your integrity really only worth $10?