You don't get to "see" the game spawn anything. No airplane launches, no DD leaving the docks. The game only "spawns" its assets outside your view, beyond the horizon, so about 30nm away, even when you're below PD.
If you're in the Stock game, on the NavMap, you can zoom-in on any identified ship and see its outline, and ascertain from its outline what it is. It may not be always 100% accurate, but more than reasonably reliable. Some mods will exchange that outline for a dot, like the leader of the tracking team doesn't have drawing skills, and just uses a dot instead. Of course, when you're on the NavMap, all you can draw is "X"s, lines & circles... Otherwise, sonar can give you a clue, as can radar, although your crew members aren't "qualified" to tell you that kind of info - you'll have to do it yourself, other than in stock the warships' sonar lines are blue, and a merchants are black. Mod can and do change that.
The game will identifiy a grouping of ships based upon the "lead" vessel. Each group has to have a "leader" that is given WayPoints for it to follow so that it can travel from Point A to Point B. All of the other ships of the group are "attached" to the "leader". If the leader is a merchant, then you have a Convoy. If you have a warship as leader, then it's a Task Force.
If you're in Stock, you will get plenty of "reports" that if you pay attention, you will get clues as to where the Task Forces are. If your are in a mod, most of them have maps laying about the boat with route maps on them. Or, you can just go hang around Truk or Rabaul, or Singapore, or Kobe, etc... Just be forewarned that the DD escorts usually have more than enough boom-boom with them, and more skill than the average Convoy jockey...
