Welcome aboard, Speedy. I don't really keep up with WWII scenarios, but I'm sure they exist. You can of course play in the Editor mode, and just start adding units to a blank canvass. It's not really hard to get started in making scenarios if you just think about what you'd like to see, where it takes place, who's going to be playing in it, when it takes place, and then start adding units to the map. Pretty soon you have started your first home-made scenario. It's like baking a cake- your first step, is to sample all the ingredients so you'll know what to add, and how much, in order to make it awesome to your own tastes.
Though surrounded by a great number of enemies
View them as a single foe
And so fight on!