What have you tried?
You can follow the grub wiki page for instructions.
If archinstall created an ESP partition, you likely used UEFI boot mode so it installed as such.

Martin

On Thu, Oct 5, 2023, 02:58 Jude DaShiell <jdashiel@panix.com> wrote:
I used it earlier since I couldn't make sense of the efi and uefi
encyclopedias in the Installation-guide.
I now have a disk with two partitions on it first one being fat32 esp.
The machine is uefi 64 capable.  For that reason I can't figure out how to
run grub-install on the latest update of grub.
Does archinstall install for bios by default?  If so, I think I can have
grub-install ignore platform and install in /boot/grub with a couple
options.  I used the archinstall that was on the latest arch release and
managed to get a working system by putting enough packages on the
essential packages line.


-- Jude <jdashiel at panix dot com> "There are four boxes to be used in
defense of liberty: soap, ballot, jury, and ammo. Please use in that
order." Ed Howdershelt 1940.