Hello: I have product images (furniture) from a photo shoot that I would like to uniformly crop and center. Meaning, I would like each product centered and have the same margins as all other like photos. Are there any helpful tools to acomplish this in Lightroom or Lightroom Classic?
You can set a resizable grid as a Loupe Overlay, in View menu. If that is set to divide the image into a certain number of squares when viewed to fit on screen, you might standardise on leaving (say) one of those squares as margin all around your product. This is separate from the grid seen when actually cropping, and only is seen again when you release the mouse after updating the crop.
Alternatively in the View menu / Loupe Overlay options you can select a loupe overlay image to do the same job. This can include your own custom framing guides, being created in other software as generally see-through (hence it would need to be saved in PNG format preserving transparency) except for some markings to indicate where and how big your "product" should sit, within the overall end output.
This overlay will keep resizing itself to always fill the frame once more, after you've updated the crop. The aspect ratios of this overlay image, and of your desired eventual crop should ideally match. Turn off the overlay image for output!