There are 2 in-game currencies in European War IV: Napoleon. Medals and Royal Emblems. Medals are earned when you complete a level according to how fast you did the level. With 5 stars you get the most medals. Royal Emblems are given when you finish one of the 5 campaigns. Medals can also be given when one plays conquest and conquers all opposing countries. Both can also be bought with real money.
When one plays a level, there are 3 resources that a player needs to win the game. Money, Industry and Food. Money can be bought with food and industry in markets and vice versa. Troops will consume food and money and industry is needed to produce units. If one earns 0 food per turn, troops will slowly lose morale and after a few turns, become confused. Do not reach this scenario.