I’ve had a Big Green Egg for 6 years or so. It’s a Kamado-style charcoal grill that is used to smoke and grill food. It can hold a pretty exact temp for many hours.
I’ve learned a lot by reading and participating in the very active BGE Facebook group.
There aren’t a lot of rules… but in general, smoking is done with indirect heat, low and slow. Grilling, by definition, is done mostly on direct heat and at a higher temp. But people cook pork butts at 225 and others at 350. I’ve done both and can’t tell much of a difference.
One very basic rule is not to cook in white smoke. Light the fire and let it burn until only clear blue smoke is coming off of it.
Another rule that most agree with is not to soak your wood. A few do, but mostly with chips and not chunks. There are endless discussion of the best brands of lump charcoal and the best varieties of wood to use.