If explaining from the ground up I would start with reconstitution basics, how much liquid per amount of powder, what the units mean, what kind of water to use, and how to calculate doses. Once comfortable discussing those points, look at protocols from sources that lay them out clearly. For the healing type, a combined version may offer better value though opinions differ on strength. The weight-loss one needs careful slow increases to avoid issues ranging from mild stomach trouble to more serious blockage.
As someone fairly new but with some knowledge gained from time spent looking into peptides, these three stand out. One for weight loss and better markers, one aimed at visceral fat, and one for shoulder and wrist discomfort. Any thoughts on how to begin using all three?