If its a short temporary pause you can press the pause button while recording then press record button.
If you need to go off the recording video camera fully then I would imagine you need to start recording again a new segment then use a video editor to combine the clips together. I am sure Samsung default apps have this function available to combine videos...
You can probably download specialised apps from the play store but if you go into Gallery and tap settings / options... there's a option to create movies or collages etc.
