Hi Michiele van der Velden,
Normally, Main Menu> Render> Make Preview, is a quick way, but it has color in it.
I have set up a scene file, that uses the Render Settings> Material Overwrite, as well as a Filter: Render Settings>Color Correction_B&W
This color correction was set up in the Picture Viewer> Filter> Create Post Effect, while setting the Saturation to -100% (equals in other applications 0%) any color will be eliminated, e.g., from lights.
Scene File:
https://www.amazon.com/clouddrive/share/DdS6pLuW6hA5PWlKVzVZYUKGEvErn5WZdR3L4Xwinlt
You can easily switch to this or back to “normal” in the Render Settings> My Render Settings. The little square on the left needs to be clicked on.
Please let me know if that works for you
All the best
P.S.: a complete white (B&W) representation that is often seen, which is a Ambient Occlusion version of the scene, but it is not fast.