When you search by initials, last name or battalion, you will be presented with a list of results. There you'll find a link to the photograph but also data like rank and pay number. The rank is usually given in an abbreviated form. The National Archives in Kew offer a list of abbreviations used in the First World War. The National Archives also hold the service records of the men interned in the Netherlands.
Most soldiers in this database belonged to the battalions Hawke, Benbow and Collingwood of the First Royal Naval Division. They were interned in a purpose-built barracks on the grounds of the Rabenhauptkazerne in Groningen, the so-called Englishman Camp. They would stay there until the end of the war.