Depending on what you mean by “very new to home assistant”, I don’t know that I would recommend this as a first project. You’re time will probably be better spent setting these up as automations using Sentence triggers. Doing it that way will mean you learn a little about trigger variable and Jinja templating which have broader applications within HA than the specifics of voice/conversation integrations.
Some Voice/Assist Resources:
HA - User Docs:
Voice Control (Make sure to check out the 20+ links in the sidebar)
Voice-related Integrations
HA - Developer Docs:
Template Sentence Syntax
Built-In Intents
Github:
Hassil
Personally I prefer using the Packages method, as I find it less complicated and more flexible than the other methods.
Regarding Question 3:
Please format your code blocks properly as directed in Questions Guideline #11, so we can tell if the syntax is correct.