Maps showing the location of all CWGC cemeteries, worldwide, are not on the CWGC website. They may be found via
http://ww1centenary.oucs.ox.ac.uk/space-into-place/commonwealth-cemeteries-of-world-war-one/.
This will be helpful if you know where the deceased’s battalion was fighting but the body was not recovered and identified. Chances are burial would be in a nearby cemetery, if the body was recovered.
Sometimes a body was recovered with the regiment known but otherwise unidentified. For each cemetery in France and Belgium, the number of unidentified burials is given in closing paragraphs of the ‘History Section.’ The website has no details on the unidentified casualties as the website search facility operates on a name search.
Thanks to the CWGC for this information.