Can I Manually instantiate a NetworkObject in Fusion?

I find that only one way to instantiate  a NetworkObject in Fusion, which is Spawn a Baked Prefab in Resource folder, How can I instantiate  a Object from Webstream, and then add NetworkObjectID and NetworkBehaviour to this Object like PUN2?

https://doc.photonengine.com/en-us/pun/v2/gameplay/instantiation