We show you a video of the invitation of Nine, by Xur in Destiny 2. You’ll get this quest from Xur, if you can not find it, here we’ll show you his current location.
You have to go through some steps, collect some samples, we’ll show you how to do the quickest.
All Steps and samples – The World Week 1
You need to defeat Taken, Fallen and Cabals for samples and complete “Lake of Shadows” strike on EDZ. There are 9 of each sample and they take a little while to drop.
You’ll most likely get the Taken and Fallen samples while doing the Strike, i’d suggest doing that first.