Sounds like you have a fine camera but I'm not familiar with it, my last point N shoot was a Canon Powershot which is roughly similar except for the specs. (Mine was a dinosaur compared to yours)
You have everything you need to take awesome pictures; it is not the camera that takes the shot but the photographer. The camera is simply a tool. You have a pretty good lens, roughly 24mm to (if one can believe the specs on Adorama, to 2000mm) with a aperture of 3.3-5.9. Lets talk about that first.
The smaller number is how large the blades open to let more light on to the sensor (or film) Yours is f3.3 when the lens is at its widest or 24mm setting and when zoomed all the way in, is at f5.9. Most 50mm lenses have 2.0, then there's 1.8 and 1.4 and so on. As those numbers get smaller the opening gets larger admitting more light meaning, you need less light to take a photograph. Since your camera is digital and not film with an ISO (light rating lets call it) this is not a big deal for you because your camera will adjust the ISO to match. Not really something to worry about.
What you may see is the tendency for the camera to take photos in auto with a slower shutter speed than you need to stop the action and make sharp photos or, with an aperture so small that everything is in focus. This is nice for landscapes but maybe not so for portraits depending on what you want to do with your photo. Note the photo by Nbanjogal; see how the pretty little girl is softly out of focus and the 'heart' is sharp drawing your attention to it? A nice photo! One that is all in focus would still be nice but the depth of field allows you to attract the viewer's eye to the heart.
The smaller the F number, the shallower the depth of field and as the number gets larger, so does the depth.
The shutter speed is how long the sensor is exposed to the scene; the higher the number the less 'exposure'. (less light AND, if its fast enough 'freezes motion)
First exercise; start with people/ things, something with something close and something far. Set your camera on A which is aperture priority. Remember that your camera will auto-focus on whatever is closer OR...it may have a small dot in the middle of the viewfinder that indicates the focus area. Whatever that is on, that's what the camera will focus on. I think your Nikon would work like my Canon did; press the shutter halfway and the focus will adjust and lock. Pressing the rest of the way takes the picture (probably with a delay, something to remember, a full size DSLR doesn't do that BTW) Take some photos using differing points of focus; foreground in focus, background and then, taking shots of the same scene, use different apertures. 3.3 5.6, 11 and so on. What you're looking for is differing depths of field, shallow to deep.
Second exercise; pick something that moves. Even traffic can be interesting IE; traffic on a road at night, the cityscape background is sharp and clear (because it isn't moving) but the traffic looks like streaks of red/white light. Use shutter priority this way, I'd suggest people walking or kids playing. Start at say, 100 and work your way up to see what speed 'freezes the motion'. Sometimes, a photo say, with the face sharp but the arms and legs slightly blurry while walking/running can be appealing for instance. The same for a running river. Take a photo of water moving at a fast (1000?) speed and its frozen. Take that same scene with 60 or even 30 or less from a tripod and the water will 'look' like its moving because it has while the shutter was open! Different cool effects.
Auto does everything, P does almost everything BUT you should be able to set certain parameters such as ISO (400 needs more light than 1600) and maybe shutter speeds/aperture ranges. Another cool exercise is night/low light photography. Use a high ISO (needs less light) and that keeps the shutter speed/aperture in a useable range. A is aperture priority meaning you set the aperture the camera selects the shutter and S is the other way, you pick the shutter the camera picks the aperture and M is full manual. you pick everything. Exposure is simply how much light a scene needs to be properly exposed. a photo taken at ISO 400 with a shutter speed of 125 and F11 is the same exposure as one taken at 500 and F5.6. They both work together to make sure the darks aren't too dark (underexposed) and the lights aren't too light (Overexposed) Your camera in auto will average, meaning it takes the middle road, because it doesn't know (like a human would) that increasing the F stop from F8 to F5.6 might make that backlit portrait you're taking just a bit better (bright backgrounds dark faces, one is probably going to be over or under) but don't you worry about that just yet. Go have fun with pictures!