The best operational series of wargames is the World@War series (Operation Crusader, Stalingrad, D-Day Operation Overlord) and its predecessor, the V4Victory series (Velikiye Luki, Utah Beach, Market Garden, and another one I can't remember). But this is an old series of games, DOS games, and you will have troubles getting it to work on modern Windows operating systems. You can probably find the games at some abandonware site. And maybe you can get the games to work on a DOS emulator like DOSBox. The games all use a planning-execution model: you plan your actions for every unit, the other side (human or AI) plans its actions, and then the game will execute those actions simultaneously or concurrently over the simulated duration of the turn. More realistic, IMHO, then moving and attacking with units one at a time, and one side at a time.
For tactical wargames, which are not really my thing, Steel Panthers and Combat Mission are the best. And Close Combat is good, too.