What are you wanting to cook (what and how much)?
The reason I ask is the PG is a grill/smoker but I wouldn't recommend the CB as a smoker. It's 100% bad@#$ grill. You have a H/M/L setting so you can't really adjust it for smoker (you couldn't but I wouldn't) the top has no insulation and you'll burn a bunch of pellets trying to get a steady temp for smoking. It's a grill.
On the CB, each 12" section get's its own burner, so for a 24 that's 2 and 36 is 3 burners. Preheat with the cast iron grates (20+ pds each one) and you get great grill marks etc.
the front of the CB is the hopper and holds the pellets. If you look at any photos on the CS website, you'll see vent holds for the fans (count them, they're for each burner). There is an auger that delivers them to the firepot (same design in every FE).