If you prefer not to use the LUN as the vmfs datastore, you can consider using a Raw Device Mapping (RDM Device) . This allows the VM to directly access the iSCSI LUN, bypassing the need for the creation of vmfs datastore.
But if you have to connet vm as iscsi initiator to target. its a good idea to isolate network with another vswitch or create a portgroup configured with vlan6.Ensure that the network connection between vm and NAS is ok and then configure the iscsi initiator on the vm. every windows os has builtin iscsi initiator software that you can add it in windows apps and features.