As @danielfrimley points out, you’ve already asked that question, in a thread I started explicitly for discussing B&W work, but which rapidly got diverted into discussion of how wonderful Leica cameras are (not) and whether it was worth feeding the Leica propaganda machine.
To summarise…
Before digital cameras were invented, we used to produce wonderful B&W images by getting to know how colour filters worked, in front of the lens, because we couldn’t change anything once the image was committed to B&W film. The viewfinder showed us a colour image because it was an optical viewfinder.
With digital cameras we can either use physical filters on the lens or apply them using FilmPack’s filter emulations. Either way, you still get to see a colour image in the viewfinder, unless you use an EVF.
You can spend a small fortune on a certain fetish B&W camera but…
- The Leica Monochrome is not supported in PL6
- The RAW file is still an RGB file, not a greyscale file
So, you would be no further forwards than taking the image with any other digital camera out there.
We still have to do what we have always had to do since the camera was invented - learn how to visualise and take B&W images.
When we shot with film, spectral sensitivity depended on the film we chose. Most film was panchromatic but we could also obtain orthochromatic film, which is unable to capture reds. Some films, like Fuji Acros 100 is defined as orthopanchromatic, which is a mixture of the two and gives it such a beautiful rendering.
Even if we use a B&W emulation on the camera (EVF or rear screen), any filters we put in front of the lens are going to work on the panchromatic level because that is what the sensor sees.
My advice - use the camera as normal and use FilmPack to choose your film and filters.
Good B&W photography relies on much more than removing colour. There’s an interesting short article here. It’s not authoritative or comprehensive, but it mentions several important fundamentals.
Final thought - good B&W images are often harder to make than good colour images and need to be visualised before you take them, if at all possible.