What are you trying to do…? No need to but Javascript Ref you will find loads FOC. NOT all will apply as ExtendScript is based on an old version.
You will need to learn the base classes as the guides don't help with any of that. They expect that you learned the basics elsewhere.
Scripting language won't change an app's behaviour changing text will do the same in given both…
Some actionmanager code may let you dig deeper but everything I've seen is a minefield with editing type…