[Discuss] I, uh, deleted the wrong kernel....

[Ben Carr]

You should have other kernels if you are Debian based unless you
removed all the others with `rm` as others have mentioned. You might
want to look into the auto-clean features of you distro, this will
allow you to say keep, 3 or 4 kernels in case one fails, such as a
regression in a driver you need. If you have no other kernels on your
system you will likely be forced to boot from other media, like USB or
CD, or DVD. You will want to install the current kernel, but also
update grub, it sounds like grub hasn't been updated. Are you building
your own kernels or using distro kernels?
-Ben