1. Some theory

The first thing you need to understand is the inverse square law.

This is that the light intensity decays quadratically (1/x^2) when you are further apart from the light source.

I normally post this diagram flipped, but I am posting it like this to match your window.

If you put a softbox to the right side of the couch the light will decrease and the far side of the room will be darker.

On a big diffuse light, this is a bit more complex to calculate that on a spotlight, but it is also true.

You then, need either to work on a large studio and put some lights further away, or you can use a softbox, take multiple shots, and compose them in post, (doing the opposite of what I did to simulate the darkening).

A. Shoot with a correct exposure of the different zones

B. Compose

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2. It seems

In the case of this image, I think it is actually natural light. Notice the reflection on the glass.

It probably has a good space in front of the window. If you have a building or a wall, this is actually the source light and the square law starts from that point.

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3. In some other cases

On a normal studio shoot of an interior, you set up multiple light sources building the interior, you normally do not rely on just one source.

This is not the case on this image. But if you cannot take several shots, as my prior explanation; if you have a moving subject, some people, you can use additional lights. In this diagram, the lights are bounced into the walls and ceiling.

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I want to point out two kinds of shadows the coach is producing.

The shadow on the left (orange) would be almost black if you only use one softbox. This is partially filled with light bouncing all over the place. In this case from the light of the other window (behind the camera)

If you are using studio lights, you need some of this fill light.