As I understand, you want to include your test directory as a mount path in your PVC. To answer that question, yes you can do it by providing it in the hostpath not the mount path. As explained in the documentation :-

A hostPath volume mounts a file or directory from the host node’s filesystem into your Pod. This is not something that most Pods will need, but it offers a powerful escape hatch for some applications.

and a mount path is -

The location in pod where the volume should be mounted.

so, if from your host system you want to mount the \test folder you need to provide it in the pv like below

kind: PersistentVolume
apiVersion: v1
metadata:
  name: task-pv-volume
  labels:
    type: local
spec:
  storageClassName: manual
  capacity:
    storage: 10Gi
  accessModes:
    - ReadWriteOnce
  hostPath:
    path: "/test"

and you can use this PV to claim a volume using pvc and use the mountPath to mount that volume into your pod.

To answer your second question, yes you can have multiple mount paths for a single PVC. An example of this which works is :-

    "containers": [
    {
        ...,
        "volumeMounts": [
         {
             "mountPath": "/mnt/1",
             "name": "v1",
             "subPath": "data/1"
         },
         {
             "mountPath": "/mnt/2",
             "name": "v1",
             "subPath": "data/2"
         }
       ]
    }
   ],
   ...,
   "volumes": [
       {
           "name": "v1",
           "persistentVolumeClaim": {
                "claimName": "testvolume"
           }
       }
     ]
  }
}