Dual Battery question

So I ordered my 7.3L powered truck with the 397amp/dual battery option. I wanted redundancy since the weather in Vegas is extremely harsh on batteries and didn’t want to be out in the middle of nowhere when a battery decides to unexpectedly die. Plus I want a winch eventually and I run off road lighting. I was a little surprised to see that meant 2 alternators. Wasn’t expecting that. Anyways not really sure how the power flows with this setup. Not even sure if I will get an alert in the truck if one fails. Is there anyone out there knowledgeable on said subject that can enlighten me?

The main reason for this post is here in the next couple of weeks I plan on installing a ARB twin air compressor. I’m wondering if I need to connect to the passenger side main battery or fine running off the secondary battery? The Ford installed positive battery terminal on the second battery does not have a connection point on it like the main battery. Makes me think you’re not supposed to run stuff off the secondary battery. I really want to be able to run off the driver side second battery since the compressor install will be on that side of the truck but want to be correct so will do whatever is needed to be correct.