Decrypt the root partition.
cryptsetup luksOpen /dev/sda2 rootcrypt
Mount the root partition.
mount /dev/mapper/rootcrypt /mnt
Mount the UEFI partition.
mount /dev/sda1 /mnt/boot/UEFI/
Mount system directories.
mount -t /proc proc /mnt/proc
mount -t /sysfs sys /mnt/sys
mount -o bind /dev /mnt/dev
mount -t /devpts pts /mnt/dev/pts
Chroot in to the system
chroot /mnt