If you're not seeing any kernel options in the GRUB2 menu during boot, it could be due to several reasons. Here are some steps you can take to troubleshoot the issue:

1. Check GRUB Configuration:

   • Open the GRUB configuration file. The location might vary, but it's typically  /etc/default/grub on Linux systems.
   • Ensure that the GRUB_HIDDEN_TIMEOUT the option is commented out or set to a reasonable value (usually 0 for no hidden timeout).
   • Verify that GRUB_TIMEOUT is set to a non-zero value if you want to see the GRUB menu.

2. Update GRUB:

   • Run the command sudo update-grub or sudo grub-mkconfig -o /boot/grub/grub.cfg to generate a new GRUB configuration.

3. Check Boot Partition:

   • Ensure that the /boot partition is properly mounted.
   • Verify if there are any kernel images in the /boot directory.

4. Check for Kernel Packages:

   • Make sure that the kernel is installed. You can do this by running dpkg -l | grep linux-image.

5. Reinstall Kernel:

   • If the kernel is missing or corrupted, you might need to reinstall it.

6. Check for Boot Loader Installation:

   • Ensure that GRUB is installed in the boot sector. You can do this using grub-install /dev/sdX (replace sdX with the appropriate drive).

7. Check for Boot Flags:

   • Verify that the boot flag is set on the boot partition. You can use a partitioning tool like fdisk or parted to check and set the boot flag.

8. Check for UEFI Compatibility:

   • If you're using UEFI, make sure that GRUB is properly configured for it.

9. Check for Other Bootloaders:

   • If you have multiple bootloaders (e.g., GRUB and another one from a different OS), ensure they are not conflicting.

10. Check for Errors on Boot:

    • If there are any error messages during the boot process, they might provide clues about what's going wrong.

11. Reinstall GRUB:

    • You might need to reinstall GRUB entirely. This process can vary depending on your specific Linux distribution.

12. Check for Disk Errors:

    • Use tools  fsck to check for and repair filesystem errors.

Remember to back up important data before making any significant changes to your system.

If none of the above steps work, please provide more specific details about your system, like the Linux distribution you're using, any recent changes you made, or any error messages you encounter during boot. This information can help in providing more targeted assistance.