Installing arch won’t give you anymore understanding of how system works, at least no more than installer would, linux systems are somewhat hard to understand especially if you aren’t deeply involved with them. Also that understanding requires so much peripheral knowledge of linux to start with, it’s not even funny. Like you can start on disk partitioning and it would take a week to explain everything you can do, look at this pie: encryption, vdo, lvm, different filesystems, billion things available in device mapper, then systemd mounts etc., etc…