Question Redundant. Ignore

Does anyone know how I can copy a pre existing mesh and skeleton that work together and have the new mesh and skeleton working together (deforming vertices)?

As right now I have to redo the names and things and I want around 500 of them on scene so renaming will be a bit infuriating.

What exactly are these “things”?

No Idea what I did wrong yesterday but its working now so no need to answer.