How to reproduce the same result from Substance Painter to Blender?

I know that I should try the Principled node but I want to understand how it works, first, because I’m a beginner.

I have seen that I have to export in PBR Glossiness-Specular, but in Substance there are many possible maps to export.
I have exported: Diffuse, Glossiness, Specular, Normal map (not world map), Height map. But I could have also exported Opacity, Curvature and others that I wouldn’t be able to implement.
Now I can barely set up the textures above, but I have many doubts because it seems that on internet all do it in a different way.

Especially, I can’t understand how to implement the Specular feature, since glossiness and specularity are both achieved in the Glossy node (and a Specular node doesn’t exist, I guess).
And, some users omit some textures. I have seen a video where the guy doesn’t use the normal map and the glossiness map.

The point is that even if I use the same environment texture with the same light, the result is much different, no matter what combination of the nodes I try. So I want to try again from 0 understanding all in a better way.

And I am quite much confused because I can’t find a complete set of all the implementations together, from where to start as base, and eventually removing/adding some nodes or textures from it.

Or, maybe, is it easier to use Metallic-Roughness and then to adapt the nodes to it?

I am a bit confused because I don’t know from where to start and what is the “base” in question.