Takes a while to get used to, but extremely fun once you do
The first thing that happened was my platoon got wiped out completely, on the first map, in the first few minutes. I was used to just about every other FPS, where you can rush into combat and kill everyone. But in this game, you die on the first or second shot. And that was just on Recruit (the easiest difficulty). It got really frustrating.
Then I realized you have to take things slowly, send a sniper ahead to scope things out, then move in for the kill. You are able to command 3 squads, though I only used the 3rd squad for my solo sniper. After taking out all the enemies piece by piece, I completed my objectives and the level. When you complete the secondary objective, you get a specialist. A specialist is a soldier with above average attributes and a different weapon. Let me explain.
Before each mission, you choose the soldiers you want to use. You can choose up to 6, between 3 squads. Each squad can have 3 people in it, though you can't exceed a total of 6 players throughout all of your squads. There are 4 classes: Sniper, demolitions, support, and rifleman. Each soldier has a class, and their weapon depends on the class they are in. They also have attributes: Weapon (how accurate they are), Stealth (how easily detected they are by the enemy), Endurance (how easily they can carry heavy equipment and how many shots they can take), and Leadership (enhances the attributes of the whole squad when soldier is appointed leader).
I haven't tried the multiplayer, because I couldn't find a game to connect to.
The game has 15 missions and 3 difficulties. The whole game is set in Eastern Europe. Overall, it's a lot of fun, though at first it isn't at all. You just need to get used to it.