It seems that all of your inquiries are deployment-related without understanding the fundamental construct as you're asking.
I need to elaborate here that Cisco ACI is not a traditional routing and switching that most of us learning from traditional Routing and Switching discipline although some underlying protocols are known to public.
You start to familiarize yourself with content from Cisco Live and search for "ACI" one that migh suit you is On-Demand Library - Cisco Live Global Events then you can moving on with other ACI topics.
There are a lot more available publicly if you're keen but I'm sure these will keep you busy for the next few months.
Have Fun!
Regards,
David Sudjiman
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