I unlocked the lvl 2 military that gives you mobile energy weapons, tanks yes?  Do they just show up on new ships that I make in my systems?  Can I somehow put some on current ships that I have out in space?

You control your land force composition through Military Screen, there, in the Troop Breakdown section you have dedicated button to decide what portion of available manpower should be used for infantry, tanks and air (providing you researched them) and you can upgrade individual unit types there as well. The troops will 'magically' have the new composition the moment you apply it, not sure how that works for already ongoing invasions.

DNLH wrote:

... not sure how that works for already ongoing invasions.

It's possible to do so same turn past solving the ground combat round.

LucidNightmare wrote:

I unlocked the lvl 2 military that gives you mobile energy weapons, tanks yes?  Do they just show up on new ships that I make in my systems?  Can I somehow put some on current ships that I have out in space?  write my research paper for me

Thanks, I will follow your directions.

I forgot about this option.