A blueprint is a “class” (essentially, a “template” that you can instantiate – very much like a blueprint for a house.)
An actor is an “object” (also known as “instance”) – very much like an actual house, built from the blueprint (class.)
“Self” inside a blueprint code execution graph, refers to the object, not the class.
If you want to “spawn a new instance of the same blueprint that created this object” then you can use “Spawn Actor From Class” and pass in “Get Class” of your current blueprint as the class to create a new instance of.
This object will create a new actor instance, that it returns as an object, that’s the object you should attach to the “current” instance of the blueprint that is going to be the parent.