If you are trying to custom features, you would typically need the SDK for the Realtek chipset used on this board, which is rarely public. Most "development" in this space involves modifying the boot logo or panel settings within the existing binary.
Download the free (from SourceForge). Run it on your PC. It will scan your camera and often reveals: Hk.t.rt2841p638 Firmware
If your version ends with a lower number than 638, or if the “rt2841p” is missing, an update may be necessary. If you are trying to custom features, you