Library and Archives Canada have put two new sets of records online for the First World War. These are “Commonwealth War Graves Registers, First World War”, and “Circumstances Of Death Registers, First World War”.
These are not databases so it is not possible to do a key word search. You need to use these links as you would use an actual microform reader. Supposedly this is to give us the experience of actually being in a reading room. Really !
If you are looking for a specific name there is a help page. Still it’s a hard slog. Reminds me of graduate school.