I found this while searching for additional Grub2 information.
The official doc about it is here > https://docs.fedoraproject.org/en-US/quick-docs/grub2-bootloader/
The link below should not replace the Docs. It should help to see where things are stored and which tooling we use with Fedora in a simple overview. If someone likes to take information from the Tutorial into our docs, please do not forget to ask the author if you pretend to copy and paste.
IMPORTANT
This guide is RHEL-family specific. RHEL 10 stores boot entries as Boot Loader Specification (BLS) snippets and expects you to manage kernels with grubby, not with Debian-style
update-grub. It does not walk through resetting the root password at the GRUB prompt—that belongs in reset root password on RHEL.
Applies to : RHEL, Rocky Linux, AlmaLinux, Oracle Linux, CentOS Stream, Fedora
Configure the GRUB2 Bootloader on RHEL
https://www.golinuxcloud.com/configure-grub2-rhel/