I already had another distro (KDE neon) installed on my disc along with Windows 10, so while installing EndeavourOS, I chose the ‘No bootloader’ option. But now the entry for EndeavourOS is not showing up in the grub menu, even after running os-prober and update-grub from KDE neon. Is there a way to fix this without reinstalling?
I would suggest installing EnOS’ Grub and letting it handle the bootloading for the other two systems.
Also the output of
sudo parted -l may help to have an idea of your disk layout.
Edit: Also it might be this: