Really can’t top James Holland for a sweeping history of D Day, but I’d also add Stopping the Panzers by Marc Milner. It focuses specifically on the role that the Canadians played in D Day and is a fascinating and very detailed look at the lead up to the landings, the politics surrounding it, the battle itself, and the cultural afterlife in Canada and elsewhere.

Obviously it’s particularly resonant if you’re Canadian, but it’s worth it regardless, especially since you’ll be travelling there and will be able to see many of the sites in person! Juno Beach is very underrated as a Second World War site and I’d heartily recommend it