In that case, you would not have a previously installed working kernel. Let's try installing one:
sudo apt install linux-headers-5.11.0-46-generic linux-image-5.11.0-46-generic linux-modules-5.11.0-46-generic linux-modules-extra-5.11.0-46-generic
Reboot and follow the procedure for entering Grub Menu:
Select the 5.11 kernel to boot from and proceed to boot - Test Youtube