If you have replications of a pod, that all need to access a shared data storage, NFS volume is one of the options.
In order to configure the storage, you need an NFS server access for your K8s cluster.
Usually you will have a remote NFS storage that your cluster uses. On that remote NFS server you get a dedicated storage space under a certain path on the file system.
Now using the NFS server hostname and the path of your remote storage, you can create a PersistentVolume for your cluster:
And to make use of that PV in your pods, you also need to create a PersistentVolumeClaim:
Now all you need to do is reference the PersistentVolumeClaim in your application's deployment configuration and mount it into the pods. This way each pod of your application will get access to this shared storage on the NFS server. So what one pod writes to it will be visible for another to read and vice versa.