Anyone who has played RTCW or ET has an edge with this game in that you are familiar with most of the available weapons, and you can swap weapons from dead enemies. By far the best are the MP40 and FG42 for both in-close skirmish and/or spray and pray, and bulk ammo can be looted off bodies plus the Axis have the best suppressed sniping rifles. And of course the panzerfaust - it really does kill tanks.
It is open world 'ish' which makes it look brilliant, but stray too far from the combat area you don't get all that much time to return, especially if flying a Spitfire or a Messerschmidt, and you get obliterated. I left flying for the birds because by the time you figured the controls you were either killed by enemy fire or the game.
Speaking of obliteration, when killed you respawn at some arbitrary check-point which can be anything like a few minutes back, or an hour of game time back. There are no manual saves which means you can spend a whole game session just repeating the one section of a mission which is very freaking annoying.
There are 4 main single player campaigns where you play both Allies and Axis, male and female, each completely different, and in very different roles. All are reasonably long so you do get quite an overall long single player game. It just a shame there is no DLC for more single player action. Multiplayer is scary, especially the 64 player maps. You seem to spawn in the middle of fire-fights and before you can figure out what is what, you get shot. So while lying there trying to think, their meds are so good you get immediately revived - and immediately shot again. There are other smaller 4 player squad multiplayer missions but they can be played online as single player against a very good enemy AI - very good.
There is way more to the game - it has a huge multiplayer start menu with so many options and with the aim of drawing punters away from other online FPS games such as GS:GO or COD.
But meh, as a single player it is still very good value for money.
Edit: I forgot to mention the graphics which are stunning and beautiful, especially when you are away from war-torn areas and in the open countryside. You can just sit and admire the scenery and listen to the birds .