As far as focus goes, use manual focus.  There are buttons on the side of the camera that allow you to zoom in, allowing you to precisely adjust which part you want in focus.  Also, you might want to check the aperture.  A wide aperture (low f-stop number) means a shallower depth of field, so if you want more to be in focus try a smaller aperture.  Experiment and see what happens!

The white balance is essentially a sort benchmark for your camera that allows it to correctly interpret colour.  Depending on the lighting, an object can look very different.  For example, a white sheet of paper will look red if held under a red light, or blue if it's held under a blue light, etc.  We know it's white because our brains process and interpret the sheet of paper.  A camera, on the other hand, isn't capable of doing this on its own and needs to be told what to do.  So you use the white balance to essentially tell the camera "this is what white looks like under these lighting conditions".*
The light itself can vary in colour temperature.  The two main settings are standard daylight (which is at 5000K [Kelvin]) and tungsten light, i.e. light-bulb light (which is at 3200K, and much warmer-looking).  It might not be immediately apparent, bu daylight is much cooler and bluish than tungsten light, so if you set the balance to 5000K and take a picture lit by tungsten bulbs it will look extremely orange.  Similarly, if you set it to 3200K and take a picture in daylight, it'll look very blue and washed-out.  Generally you want to aim to get the WB setting as close to the lighting conditions as possible so the picture looks as accurate as possible (though if you want to your scene to have a warmer or cooler look you might want to set the WB slightly higher or lower to achieve this effect).

Hope this makes sense.

*You can use auto white balance to skip having to manually change it, though I wouldn't recommend it since manua gives you a lot more control.