Hi Jerseygirl!
If you click on the career tab for your Sim (lower right corner), you'll see the metrics needed for the current level of his career. For military, I believe it's only Handiness and Athletic, depending on the level. You'll see little smiley faces next to each metric that tell you how well your Sim is doing. Work on those skills and level them up to see increases in the job metrics. This helps your Sim get promotions faster. You can also set the tone of the workday by selecting from the drop down menu in the upper left corner while he's at work. It can be Business as Usual, Work Hard, Chat with Co-workers, etc. The Work Hard tone will help your Sim advance to the next career level faster, but he will be more stressed out because of it.
As for the babysitter, there are probably few interactions because she's a teenager. There will never be romantic interactions available between an adult and a teenager. To befriend her, just keep using the interactions that are available and others will likely appear as the relationship bar advances.
I hope this helps!
