On the server (host)
# gets uid and gid of the user nobody, which will be the owner of the NFS share
$ id nobody
# adjust the permissions on the folder that will be served by NFS
$ chown -R nobody:nogroup /nfs/public
$ chmod -R 777 /nfs/public
$ apt install nfs-kernel-server
# below is the file that has the list of the NFS shares
$ nvim /etc/exports
/nfs/public *(rw,sync,no_subtree_check,anonuid=65534,anongid=65534)
$ systemctl restart nfs-kernel-server
On each client (e.g. Proxmox KVM guest)
$ apt update
$ apt install nfs-common
# folder on which the remote NFS share will be mounted into
$ mkdir /mnt/public
# add an entry to /etc/fstab, so it can be automatically mounted if available
$ nvim /etc/fstab
[Proxmox_Host_IP_here]:/nfs/public /mnt/public nfs defaults,nofail 0 0