[CanadianSal]

I am not sure what this is called. This is the post at the top of my stairs.
This is a bit shaky and I am wondering how do I stabilize it?
Advice appreciated.

 

[Windows on Wash]

Pocket screws.

 

[Nealtw]

It is a newel post, it might be set into the framing below or anyone of a dozen types of hardware holding it in place.

So first look for nail holes, plugs that hide hardware or anything.