may seem a stupid question but what is the difference between the different lvl of badges, and how do you tell which ones you are going to get? (How do you get higher lvls?)
There are no stupid questions, just stupid people who ask questions
The difference between badges is what they can buy. Each one goes with a rank. So the first order goes with LT and buys Mk II stuff. The second order goes with Lt. Commander and buys Mk IV. And so on. The one exception to this is Mk VIII shields, which are bought with 3rd order badges, most likely a bug, should be 4th order.
You can tell which ones you are going to get by looking at the rewards for the mission before you accept it.
Each of those missions goes with a certain "unexplored" area. The first two are level 4 and 8, Lt. Levels, reward First order. The last one is for the zone located next to where the highest level missions are and awards 5th order badges. So just picking the right mission will let you get the appropriate badge you are after, assuming you are high enough level to get said mission.
You can check how many you have in your character's status window, under the progress heading. Not something you asked, but thought I'd throw that out there.