OK, since you are using the V2 classic app, I suggest you read the following two community FAQs. They should answer your initial questions. ( in each case, the topic title is a clickable link)
Before that, though, the shortest answer is that you can set up automations for almost everything using the official “smart Lights” feature in either app ( also called “smart lighting“: they’re the same thing) , and using “custom automations” in the new V3 app or “routines” in the V2 classic app. You don’t need a separate smart app for each individual device. All those different lights and switches can have rules set up for them using the smart lights feature. So see if these help.
