Nobara by default includes the Nvidia modules in the initramfs to prevent no video issues during LUKS password entry. This ends up taking a lot of space on the /boot partition, especially so if it's coupled with an iGPU.
If you don't use LUKS and want to free up space for more kernels and/or your 1GB (older default size) /boot partition is full and you can no longer update the kernel you have 2 options.
Open Driver Manager (or run nobara-driver-tui in a terminal) and Install this profile shown in the screenshot

If for some reason you have no Internet connectivity in the state your system is at the moment, proceed with Method B.
echo 'omit_drivers+=" nvidia nvidia_drm nvidia_modeset nvidia_peermem nvidia_uvm "' | sudo tee /usr/lib/dracut/dracut.conf.d/99-nvidia-module.conf
sudo dracut -f --regenerate-all
For this method, you can follow this guide Nobara Kernel Fallback