NFS shares directories over a network. Add exports to /etc/exports and run exportfs -a on the server. Mount on the client with mount -t nfs4 server:/path /mnt/share or add to /etc/fstab for persistence.
NFS — Network File System
# Server side
sudo apt install nfs-kernel-server
echo "/var/www 192.168.1.0/24(rw,sync)" >> /etc/exports
sudo exportfs -ra
# Client side
sudo apt install nfs-common
mount server:/var/www /mnt/web