Asteroid Mining Ships need an asteroid mining module.
They will just dump the mined minerals onto the Rock they are mining from, unless you have cargoholds in which to load it.
I don't know if they'd prefer the cargoholds, though, I don't think so. Use massdrivers.
Mass Drivers are just put on a planet.
When one is in place, in the economics window there is a mining tab, you can set a massdriver destination there.
One is needed on the receiving end to catch those mineral packets.
ALWAYS make sure you have one, or you will bombard that planet with huge chunks of rock.
Officers of any kind are automatically created, if you need more, build more academies.
As for actual "Training", Scientists eventually grow better if they have a job to do, so if you have a spare lab and a spare scientist...
Same is probably true for Administrators; Naval Officers and Ground Forces Officers train by doing something.
Combat is a good idea, but you can also create teams, like Spy, or Diplomacy, etc.... Those gain experience when they do something as well.
To colonize mars, you unload structures there.
I'd start with "Infrastructure", a cheap 'structure' that supports population, depending on the colony cost.
Then, you start shipping over colonists and other Installations, like mines or the like.
To create a Team, go to the planet in question, go to the teams Tab, I think it's also in the economics screen, then pick the kind of team you need, and a bunch of unoccupied officers that have skills in the matter.
In case of Geo Teams, let them train on unimportant sites, before you survey the more valueable targets.