See the manual (page 141) about Remote Duration on.
It is NOT about shutter duration. The shutter duration will be which ever shutter speed you set on the camera. The remote is just a trigger, not a timer. You can set the camera shutter to be open duration of 5 or 10 or 30 seconds. The shutter numbers shown with a " mark are seconds. Those without the " mark are 1/seconds. Saying...
30 is 1/30 second, and 30" is 30 seconds.
Remote Duration is the timeout to when it turns itself off, if idle, when you have to turn it back on to use it again. I think this is a battery consideration.
Sorry, there are two PDF manuals at
Nikon | Download center | D3200
One is a small User Manual, which I suppose is what ships with the camera?
The other is called a Reference Manual. Similar, some content is the same, but it is greatly larger and more detailed and complete. If there was a CD with the camera, possibly it is there, but you can also download it above. The PDF is very handy, because it is text searchable.
Also what is Rangefinder?
As relating the D3200, see the Reference Manual page 142.
The Index in the back can find most such terms. Also text search of the PDF finds it.
This one can use the Exposure indicator in the viewfnder as a focusing aid for Manual focus mode.