I tried to comment on this post but I don't have enough reputation. I'm having the same issue as that user, except that I can't find my /etc/crypttab directory and I can't find my /etc/fstab directory either.
Some additional info:
I have several drives in my PC, and I believe I'm mounting the right one when I follow the answer in the linked post. However, when I get to sudo mount /dev/nvme0n1p2 /mnt/boot/efi
I get a "mount point does not exist" error.