I mostly learned from some of the terminal customization which came stock with Manjaro when I was first learning Linux. So when I made the jump to Arch, I customized my terminal with fsh with the powerlevel10k theme and text highlighting. I also modified some of the default text colors to a green color to evoke green phosphor CRT terminals.

Daily Arch user here. The process of configuring an Arch install is perhaps not as difficult or mystical as you are imagining. I would say it is more like your first analogy: picking what off-the-shelf parts you want for a system and then putting them into a case. I think what you are describing is more like Linux from Scratch.

Installing Arch is effectively taking the steps performed by the installer .iso disks which every distro uses and instead doing it manually with CLI commands. You use CLI commands to partition the drive, create a filesystem, install a basic set of packages, then chroot into your system and use the package manager to install the rest of the packages you want. Aside from editing a couple config files, there is zero coding involved. The exact steps vary from guide to guide, but a basic outline of what I do is as follows:

• First, I download the Arch iso and write it to a USB.

• Once I boot up the install USB, I use iwctl to connect to my wifi for the packages I will need to download,

• then I use fdisk to partition the drive I want to install to with an EFI and linux filesystem partition (You might also make a swap partition at this step but I typically use a swap file on my filesystem partition).

• then you use mkfs to create filesystems on the EFI and linux filesystem partitions.

• Then I use genfstab to make the /etc/fstab file

• Then, I use pacstrap to install the base packages like pacman. Then I mount the filesystem and chroot into the new partition.

• From there, I basically use pacman to install all the packages I need, including the linux kernel (I use linux-zen), the DE (I use KDE), the boot manager (I use Refind), and everything else. There are a few cleanup steps like setting the locales and time zones, etc. but that is about it.

I suggest watching a guide on youtube, which was how I learned, or installing something like Arcolinux or Endeavour, which simplifies the installer into a series of checkboxes to select what DE you want, etc.