VIDEO SYNC

DOES ANYONE KNOW HOW TO DO ANY OF THESE 2 THINGS. 1. IMPORT VIDEO SO THAT YOU CAN EXTRACT THE AUDIO AND REPLACE IT WITH THE RECORDED AUDIO FROM THE CUBASE 9 DAW…2. SYNC SAID AUDIO TO THE VIDEO SO THE VIDEO PLAYS BACK WITH THE RECORDED AUDIO FROM THE DAW

If I understand the question properly…You cannot replace the audio of a video file using Cubase.
You can of course record audio in sync with a video and then render your mixed audio with the video using a video editor.