Not sure what you mean by "relate his date of birth to military records" as the keys for finding a person's records (service or pension) are his regiment and regimental number.
From his Medal Index Card (attached) from free search on Ancestry simply using full name and regiment, his number is 2113.
The card indicates he qualified for the 1914 Star with clasp & rosette (indicating he came under fire) and the British War & Victory Medals.
From the note on the back of the card he may have been serving with the 7th Field Company R.E.
A search with full name, number and regiment for WWI service files gave nil returns, same search for pension file indicates 1st record returned likely to his.
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