The INDI Control Panel is a low level interface to the device driver and much of what is on it reflects the coding interface to the device. The layout is largely auto-generated and terminology is almost entirely up to the developer of the driver. Every driver is different so documenting them would be very difficult. There is good documentation aimed at the developers of device drivers.
Some parts of the interface are standardised so that applications like EKOS can wotk with devices from multiple suppliers.
If you are using EKOS (or indeed any other application) you normally would not need to use the INDI control panel much, if at all, as EKOS would send the required settings to the driver and these would show up in the control panel.
As to the specifics of the SVBONY control panel I would interpret it as follows:
Stream On/Off means the video is displayed on screen but is not saved to a file.
Record saves the video to a file.
Record On starts recording until Record Off is used.
Record (Duration) records for the specified number of seconds or until record Off is used.
Record (Frames) records the specified number of frames or until Record Off is used.
Whether FPS is controllable or not depends on the device capabilities. In this case it looks like you set the exposure time and the device decides the frame rate.
WCS is World Coordinate System. As I recall it is used to save RA and Dec in the FITS header when you are imaging. The WCS tab lets you enable or disable this standrad feature.