Useful guide how migrate from EndeavourOS to Arch Linux .
Here you can see guide, forked by me, which more updated than old guide.
Technically that is not quite correct because Arch does not include yay by default and it does not use dracut.
Arch is a distro, where you can customise all, so even if Archinstall not include this option, I think it support it,similar to yay.
Why not just use Arch to start with? Seems like a lot of effort To go where you should have started.
It is not about supporting it is about migrating . And I think your method is just not sufficient to do that.
I dont see any reason why someone would do this. Like what would change? Isnt it like, the thing with EOS that its like as close to arch as possible? Only the difference that its easy to install and comes with packages 99.9% of people use anyway? and make some stuff a bit easier? so… whats the point?
Like the only thing i see myself doing, SHOULD some certain things happen in the future that are related to systemd and some other things, is that i would consider migrating to artix, but that only if these certain things happen. else, i will stay till i grow a long grey beard and look like merlin or gandalf
If someone does not like the choices EOS makes, just use Arch from the get go. Or, choose one of the dozens of other options for an easier Arch install that makes choices closer to your liking. I don’t see the point in choosing a distro just to change it into something else. Arch itself gives your the power to choose exactly what you want, just start with Arch.
Installing yay on arch is not that straight forward as it might seem just look at this link.
If those instructions seem complex, then using yay is probably not a great thing. Those instructions are about as basic as it gets to manually install something from the AUR. Familiarity with the manual method of installing packages from the AUR should be a prerequisite for using the AUR. If you want to call this gatekeeping, then so be it.
Don’t get me wrong I just think the topic starter has the wrong perspective about this migrating thing, and I just gave a example of that, it’s not always as simple as one might think.
I’m also little bit dumbfounded why this is necessary. I don’t say that it has no place, I simply don’t see reason why to do this.
I have used and installed both EOS and Arch numerous times (and will do many times in the future); my experience is that differences that “pure” and EOS have are mostly under the hood that most users don’t even think about or rarely need to tamper in basic use after getting system up and running.
Archinstall has made installation of Arch easier than it was “in the good old days”. Although I’m not certain if they actually were good, but anyway.
As others have said, EOS is as close as “pure” Arch that it can be with sensible utils that make life easier, not that it’s in the end that complicated in Arch. You just need some more labor to do things.
So I don’t see reason for this, because it actually doesn’t change EOS to Arch, at least in “pure” way. But I’m not saying this is a bad thing.
If I had to rate this with regard to usefulness, I’d give it a 2 out of 10. However, any knowledge has SOME use and some intrinsic value.
I don’t see the point to this “guide” and why would you want to move away from EOS?
As a experiment? 
EndeavourOS is the best of Arch made better and easier! 
You can hear sounds from UEFI of my PC when I tried to run Debian or Arch images.
No I can’t.
But I can do this, so I cannot install DEbian/Arch even with disabled secure boot(Dell Vostro ).
If you know how fix it, share idea , I will happy to know
That looks about as straight forward as straight forward can get.
Without knowing the details of what the actual issue is it’s going to be impossible for me to guess. But if you can get One OS installed you should have no issue installing any other OS. Perhaps you should start a thread explaining the exact issue your having. Be sure to include system specs and any logs if applicable.
This sounds odd, because Debian supports secure boot.
But as @thefrog said, it’s hard to start digging into this without any info.