Know very little about cameras, need advice?

The exposure of the light sensor in digital or the film in analog cameras depend from the amount of light coming through the objective. It can be regulated by opening/closing the aperture or shortening/prolonging its opening time. The wideness of the aperture is expressed in numbers starting at 1.2 going until 32. 1.2 is wide open for night shots, 32 is for shots on the Atlantic Ocean in Miami Beach. Alternatively opening times can be regulated from 1/10.000 of a second to hours of opening time. One more necessary parameter is the light sensitivity indicated in ISO. For normal daylight a value of 100 is common. Digital cameras go across 2000, 1200 already is a night vision device.

One over the thumb rule is on a sunny,not too sunny day shooting a person with 100 ISO requires an aperture of 11 and an exposure time of 1/125 sec. From this "Point3 you are able to move into any direction. I it starts raining, aperture is reduced to 8.0 or 5.6; time is left as it is. Alternatively the aperture "11" is left, time is increased to 1/60 or 1/30 sec ((every step doubles the amount of light coming in). Your problem start at this point. 1/60 sec and above cannot be held by hand without

blur. Having no tripod you would prefer to leave the time at 1/125 an open aperture until its maximum (opening aperture reduces a pictures "deepness", the range of the image being sharply focused)/

Here comes the machine. "P" means "Program", the machine controls everything. The results will be Technical good but standard images. "M" is fully manual for experimenters. TV is "Time pres election", the camera adjusting the aperture, AV is "aperture preselect ion", the camera adjusts the opening time. Portrait and Landscape depends on how you hold the camera. AF is "Auto Focus", the camera adjusting the sharpness. DON'T try this by hand in an AF objective.

Cameras refusing to shoot either have the timer activated ('for self portraits), the SSD card is full, missing or corrupt, or a preselect ion of time or aperture was chosen which has no corresponding value for the camera to be adjusted. (Modern cameras refuse to take bad pictures. What a nightmare).

The choice of the image orientation is for the display on the back. The camera then needs to read the complete card and the processor is so busy that you cannot take pictures on the other side.

If any problem still exists check if the battery is loaded, nobody holds the AF objective of the focus ring, if an exposure time of 1/50.0000 sec was chosen for a night shot etc etc.

For beginners the best is "P". With digital cameras it costs absolutely nothing to play around. Any bad shot simply is deleted. Therefore after "P" I would quickly move to"M" (not for shooting something important like sister's marriage).

For this an expert would take AV or TV depending from his taste.

PS: Focus length. 50 mm is like we see it. Below is wide angle (12 mm is called "Fish Eye"), above is Tele. With 1000 mm you are able to make passport photos of the space shuttle crew. For persons always use aq Tele. They behave more natural being shot from a distance of 500 yards not knowing that a portrait is taken/

The BEST thing to do is look at the camera for a brand and model number (Canon, Nikon, Pentax...T1i. T2i. 3100, 5100, Kx-r, etcetera) and then go to the appropriate manufacturers website and download the manual for the camera and read it cover to cover.

The manual will explain all of the basics to you...including what features work with what functions.

Download a manual from the offical website of the camera's brand.