Installing
2. Installing GRUB Customizer
Then to Install GRUB Customizer in Fedora
Simply play:sudo dnf install grub-customizer
Authenticate with the User Admin Pass.
If Got “User is Not in Sudoers file” then Look: Solution3. Launching GRUB Customizer
Finally, Launch & Enjoy GRUB Customizer.
Or from Shell with:
grub-customizer

So Now I am truly Happy if My Guide could Help you to Quick-Start with GRUB Customizer on Fedora 37!