If i move a U.S. destroyer into a sea space that has an a German sub and several U.K. sea units(no destroyer in the U.K. fleet) do i conduct combat?
If so, how do i go about doing so?

On a larger scale, how do the Allies subdue/ beat the Germans before the Japanese take Russia and make it damn near impossible to do offensive actions in Europe?

Bare in mind i play without bids, and i am well aware of the game imbalances that exiest when all five players know what they are doing, but my group doesn’t quite know what it needs to be doing to play the game effectively.