I'm Running a Published Adventure

You'll find guidance in Chapter 1 specifically for running published adventures, and most of the advice in that chapter about running a game applies to published adventures. The information in Chapter 3 introduces the galaxy that you'll find featured in Starfinder's published stories. Scenarios in the Starfinder Society Organized Play program and Starfinder Adventures use the subsystems in Chapter 4. The Victory Points subsystem is the most fundamental of these, but many adventures also use the other subsystems found there for things like chases, vehicles, hacking, and cinematic starship combat.