Here we have a simple scene in blender with just a sphere and a camera that is pointing
at that sphere.
And when we go over to the rendered view up here, and this is with cycles render.
You're going to notice that everything looks grey and boring, and this is not what we want.
So what we want to do is setup an hdri so this sphere has some lighting and some reflections
to play with.
So what you're going to do is go over to the shading tab.
Go from object to world.
So this is now affecting the environment.
We are going to delete this background node so just click x.
Then click shift a to add.
Go to texture.
Go to environment texture.
So now we have an environment texture which we are going to plug into the surface.
And now all we need to do is select our hdr file.
So click open.
For me I have one on the desktop so navigate to wherever you have one.
And then just double click.
So now we have this hdri installed, but of course we don't see anything.
It just kind of looks boring.
That's because we are not in the rendered view.
So just click rendered view.
And it's going to take a second.
And notice that this is spherically wrapped.
It's not just like a plane.
This wraps all the way around and we have lighting and reflections on our sphere.
And make sure this is set to equirectangular if it isn't.
But it should be by default.
So just to really stress the point, what I'm going to do is I'm going to take this sphere.
I'm going to object.
And then I'm just going to manipulate this material so we can see more reflections.
So we want to make it really metallic and we want to make it really shiny.
Drop the roughness.
And there you go.
Now we have this metal marble or whatever you want to call it.
And you can really see these reflections which are all being wrapped correctly.
And then if we go back over to world, of course we can always just replace this image with
any hdri and then it will always setup like this.
And notice that if we go back to layout.
I'm going to enable our camera so we are looking this way.
And again we have our hdri applied.
And hit f12 for render.
It's going to take a second since it's cycles.
But notice that this render pretty much includes our reflections and then it also includes
our background over here.
And of course if you want this background to look less low-res, you need a very high
res hdri because it's wrapping around a giant sphere.
So you need it to have a very high base resolution.
We can just close that up.
But that is how you setup hdri lighting in blender.
Hope this helped.