you need a tripod if you’re planning on getting tack sharp images.
Use the aperture to pull your subject away from the background.
You say that you don’t have the best lens – the “thrifty-fifty” can aid you in producing magnificent shots. If you know how to use it.
The 7D has the ability to make and store micro-adjustments to the AF system for each lens you have. This video will get you started: