Hey Tony and welcome to our own little world of chaos.
Battle Dawn Forumsviewforum.php?f=45
Here you might want to visit introduction to, well, introduce yourself.
Also visit the Game Guides and Strategy & player-guide sections, and newbie questions boards.
There is also a mentor "program" you can join called Adapt-a-newb. They'll teach you what you need to know.viewtopic.php?f=47&t=1036
As for the last question. That all depends on how many units they have defending their outpost (OP).
But if no one is defending it than any 1 unit can capture it.