If you mean the exact node instance you create, then no, the node is what it is, one can only exists in one place, because itself is an individual.
If you mean the node instances with the same type, for example, monster slime, and you want have this kind of monsters in different scenes, then yes. Save the scene and you simple do instancing through either the editor (The link like icon) directly or using add_child() in code.
Usually, when we want the same instance to be in different place (Exactly the same), that's what's called referencing, this may be done in code. You reference the node using variable like var NODE = get_node("/root/..../My_Node"). It can exists in different scripts, but not in different scenes. (Like a person can't exists at two different places at the same time, but the person's properties and infos can exist on different devices. When you send him 1$, you can send to his ACCOUNT1, ACCOUNT2....)