Define "advanced".
Otherwise, just go with Debian, or Linux Mint
From Wikipedia, the free encyclopedia
Linux is a family of open source Unix-like operating systems based on the Linux kernel, an operating system kernel first released on September 17, 1991 by Linus Torvalds. Linux is typically packaged in a Linux distribution (or distro for short).
Distributions include the Linux kernel and supporting system software and libraries, many of which are provided by the GNU Project. Many Linux distributions use the word "Linux" in their name, but the Free Software Foundation uses the name GNU/Linux to emphasize the importance of GNU software, causing some controversy.
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Define "advanced".
Otherwise, just go with Debian, or Linux Mint
If you’re just looking to learn something new, why not try an immutable OS like Fedora Silverblue? It’s an easier install than Arch, obviously, but there’s lots of differences from a standard distro. There’s security upsides but also consequences to work around.
Speaking of immutable, I'm surprised nobody has suggested Endless yet, which I don't know much about but is usually suggested in these kinds of threads, and it's immutable. You might want the ISO with the smaller size if you don't want to basically download Wikipedia.
Assuming your goal is to gain knowledge about operating systems
Try arch but without kde, gnome, xfce, lxqt... make your own DE, based on a WM of your choice. That way you'll gain lods of knowledge about how an OS interacts with the user and which applications do what.
After that, you would have to go for LFS or Tannenbaums Modern Operating Systems
LFS and Gentoo, you have to compile, sure... but Arch? You don't compile the kernel on vanilla Arch, if you mean packages, then just get the *-bin
versions.
Edit: misunderstood your post. What's wrong with Arch and Arch-based distros?
I phrased that wrong, I just edited it to reflect what I wanted to say.
I have to shamelessly plug for Arch Linux here. I think Arch would be a great way to get into the more advanced side of Linux without quite delving into the complexities of LFS.