Lightroom is not designed to read and import the images from Photos Application, it was only till iPhotos, that Lightroom could read the Library of iPhotos.
So you need to export the image out of Photos and then import in Lightroom .
Thank you so much for your answer.
Can you recommend how to/ where to export the pictures to (so that I can use light room)?
You may export the images to an External Drive as that will save storage getting full on your computer.
And then import them in Lightroom.