Pretty new to linux. Actually my son set this machine up, but not available to me now and I have trouble. I get an error message on boot that the boot disk is full. Now it is so full I cannot even look at installed software, because it throws error messages, inviting to fix it, but just wraps around.
So after some quality Google time I found how to list the disk, (ls /boot) and it appears I have seven kernels, about the same number of grubs, etc, which I assume is why the boot disk is full. BTW: it is a partition on a nearly empty 2TB drive,. Again from a Google hit I tried
Sudo apt-get autoremove
but it did not cure the issue. Tried to install synaptic, which is supposed to remove selected kernels, but cannot install anything. So I don't know if I somehow need to resize the boot disk, delete old kernels, or ???