There's really not too much tutoring going on, especially in the Rescue Hostage exercises. You are placed in the environment and expected to practice until you consistently achieve a positive outcome. When bursting into a room, depend upon about one half-second to get your gun on the target and squeeze the trigger, or you're dead. Opposite rooms in the office complex are a real bear because as you enter one room, your back is facing the other doorway. Rookie level has a primary objective.
Veteran adds a secondary objective.
Expert adds more terrorists and demands a high level of expertise and success. The Planning Phase is a jaw-dropper, but it's pretty easy to get a handle on. The first four missions have default mission plans for your convenience. It's very helpful to see a plan already laid out. By the fifth mission, you should be ready to create your own.