Here you can read how to unlock additional fields / slots to be able to prepare more operations after your agents have completed their missions. Thanks to this, you will be able to prepare as many as five operations for use during the game.
When your Agents infiltrate various institutions, you unlock more Missions on which you can send agents. If the mission is successful, you'll unlock an Operation. Operations can be activated at any time and most often they are activities supporting military operations or they are aimed at sabotaging a hostile region. Therefore, it is worth having many prepared operations that will tip the tide at a critical moment. By default, however, you only have 3 operation slots.
To get 5 operations slots, you need to build a base building: Intelligence Agency. It will be possible only when you reach 2000 points of Hegemony and you will accumulate 1500 Solari and 500 Plascrete. In addition, you must complete the research: Espionage Logistics from the blue development tree, which gives you the opportunity to build the aforementioned building.