Homebrige is just a translator.
if you think of homekit as a language like Spanish, it's a little easier. (It's not actually in Spanish, just an example)
it really is just a basic language though, although all the words are in English, There are just certain ways that the request has to be formatted. and certain words you have to use.
to try and make it simpler...
Say the Home app speaks Spanish,
native Homekit devices can also speak Spanish, so it's easy for the home app and them to talk back and forth.
Some devices can speak multiple language, like Spanish and French (or homekit and Alexa) so multiple things are able to control them.
Other devices might not speak Spanish, only German. Like a Nest thermostat.
That's when you'll need Homebridge to translate between Spanish and German.
Homebrige plugins are just language packs, so if you need to add a new language like Nest/German or "your TV"/Italian, you just add the plugin.
once a device has gone through the translator, it's just another homekit device that you deal with the same way as a regular homekit device.
Add it to the home app, and then add scenes or automations.
Each plugin should have configuration options on the GitHub page for that plugin, and every one of them is a bit different, so there is no "basic plugin configuration" You'll need to ask about a specific plugin and problem you're having.
Every install of homebridge is a bit different, due to the many combinations of plugins available, You'll have to figure out your own combination.
If you can get native homekit, by all means go that way. Don't think of homebridge as something you HAVE to have.
Don't start by saying "I want to install homebridge."
First think about what you want to accomplish, like turning on a light or controlling your TV. And then decide if homebridge is the way to make that happen.
