apt-get install cifs-utils -y

mkdir /mnt/YOURCHOSENAME

mount -t cifs -o user=SMBUSER //ip-address/directory /mnt/YOURCHOSENDIRECTORY

pct set LXCID -mp0 /mnt/YOURCHOSEDIRECTORY,mp=/DIRECTORYINCONTAINER

mkdir /mnt/nas-movies

mount -t cifs -o user=proxmox //192.168.20.200/movies /mnt/nas-movies

pct set 231 -mp0 /mnt/nas-movies,mp=/movies