Can't boot Linux Mint via grub>

[mountainranger]

I did updates and restarted my computer only to be faced with GNU GRUB 2.04. I tried to see what is there. ls it came up with (hd0) (hd0,msdos1) hd0,msdos5) (fd0). I figured out that my linux file is (hd0,5). This is the one I want to boot, but I don't know the kernel command.
I saw some instructions on https://www.linuxfoundation.org/blog/bl ... 2-on-linux, so I followed the prompts.

It said
set root=(hd0,5)
linux /boot/vmlinuz-3.13.0-29-generic root=/dev/sda5
initrd /boot/initrd.img-3.13-29-generic
boot

I tried to follow the prompts but I got stuck at the second line. Grub replied "error file 'boot/vmlinuz-3.13.0-29-generic' not found". The truth is I have no idea what the 'vmlinuz-3.13.0-29-' is supposed to mean. The link above advises this: "The second line tells GRUB the location of the kernel you want to use. Start typing /boot/vmli, and then use tab-completion to fill in the rest." Well, there was no tab-completion for me.
So, my question is: how can I complete this process and get back to my Linux Mint 20.3?
Any advice is appreciated.
Michal

[Jo-con-Ël]

You can not figure, you must be sure about:

1)Mint's root partition with ls (hd0,msdos5)/ result. It will list Mint system folders (bin, boot,...)

2)Installed kernels on your system with ls (hd0,msdos5)/boot/ result. Then replace vmlinuz-3.13.0-29-generic and initrd.img-3.13-29-generic on codes with real ones (most probably. 5.4.0-XXX and/or 5.15.0-XXX ).

Also see this, but I would boot Linux Mint 20.3 Live USB and run Boot Repair after checking/repairing Mint's root filesystem (on terminal if sda5 is Mint't root as per sudo parted -l result, running sudo fsck -y /dev/sda5)