I'm running Ubuntu Live USB right now. My SSD has Ubuntu installed on it, but it's having boot issues. I want to login to this SSD so I can run some updates. I was able to do this yesterday but I lost the command I used. I don't want to do this from the Grub screen or full CLI login.
I want to run sudo apt update and some other commands on my SSD, not the Live USB I'm running.
From the comments @oldfred and @Raffa this worked for me.
sudo mount /dev/sda1 /mnt/
sudo mount --bind /proc/ /mnt/proc/
sudo mount --bind /sys/ /mnt/sys/
sudo mount --bind /dev/ /mnt/dev/
sudo mkdir -p /mnt/boot/efi #Create EFI partition mount point
sudo mount /dev/sda1 /mnt/boot/efi
sudo cp /etc/resolv.conf /mnt/etc/resolv.conf
sudo chroot /mnt/
dpkg --configure -a
apt update (no sudo)