Welcome! You don't just have to rely on other people's words - if you just got the game on Steam, you can hop in the beta yourself right now!
There's a manual in the game's directory which should help.
It might be best to start a new LAN server with the AI set to None to play with the units and read their tooltips, and try their skills out before you jump into fighting against a person or the AI. The game takes a bit of getting used to, but if you've ever played RTS's, like Starcraft 2 for instance, a lot of the helpful UI features are in this game as well.
