When I opened the Project Settings to specify the Default Maps, I couldn’t find the Template_Default level and I do have Show Engine Content enabled. I think this may have happened after I deleted the content in the folder
%appdata%/local/UnrealEngine
but I read that the content in that folder is supposed to get regenerated automatically. When I browsed to the folder the template map is contained in Engine Content/Maps/Templates in the Content Browser, it appeared again in the project settings dropdown menu.