Is a 100x100 px image with 100 ppi equal to a 71x71 px with 50ppi?

This should be obvious but the content out there on the web is confusing.

I'm trying to understand the role ppi plays when saving an image.

So if I have an image with rows of 1000 pixels, is it the same resolution if there's 100 ppi as when there's 300 ppi? Or is the 300 ppi higher resolution, since the pixels are more packed together?

Or on the other hand, are there more total pixels when there are 300 ppi or is that like asking if a pound of feathers weighs more than a pound of gold?

I'd really appreciate some help clarifying.