I am not familiar with UTM, but if you want to use it for gaming, 86Box might work better because it supports 3D acceleration.
I think that means that the built-in speakers and microphone won't work, but a USB DAC with external speakers and Bluetooth audio devices might work.
You can't install Termux but you don't need to - postmarketOS already is a Linux distro, so you can do anything you could do with Termux
That one uses a different SoC, so it has a different wiki page: https://wiki.postmarketos.org/wiki/Samsung_Galaxy_SIII_mini_Value_Edition_(samsung-i8200)
I think the features you'd need for Pi-hole should work: https://wiki.postmarketos.org/wiki/Samsung_Galaxy_S_III_mini_(samsung-golden)
You could install postmarketOS on it and use it to run Pi-hole
"Bruder muss los"
Der Rest ergibt sich implizit.
You only need mount points in each distro for partitions that you want to be able to access from that distro. If you don't need access to your Arch system files from Debian, don't mount the Arch partition in Debian.
But if you have a partition that you want to access from multiple distros, you don't need to use the same mountpoint in each distro - just like a USB flash drive can be E:\ on one Windows computer and H:\ on another - that is just a name and the files on it are the same.
Mount points are specific to one install - for example, you can mount your Manjaro root partition as /mnt/manjaro on Fedora. From every distro's perspective, the partition it is installed on is /.
You seem to be mixing up the locations of partitions and mount points - a partition is somewhere on a disk and a mount point is basically a sign that points to it, and every distro can have different signs that point to the same thing.
You can only mount one partition at one mount point, but any empty directory on one partition can be a mount point for another partition.
GPT is a partition table and is not used for Linux specifically, but on any computer with UEFI - it defines how to find partitions on a disk, but not how they are formatted.
ext4 is a filesystem - formatting a partition with ext4 means creating data structures that tell the OS where to find files and directories in the partition.
It's similar to how drive letters work in Windows: the partition you installed it on is C:\ and you can assign any other letter to any other partition.
On Linux, the partition you installed it on is / and you can mount other partitions in any empty directory.
It should always cause a syntax error if the code contains
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