I used screen recording and did not realize that I had to turn on the microphone. Is there anyway I can get sound on this recorded video

No.

LenitaM2015 wrote:

I was listening to a livestream training and the audio is missing. Can this be rectified

No.

There is no sound recorded in what you have now, so you'll either need to re-record the contents, or find some other existing recording of the sound and add it onto the recording using iMovie or another movie-editing tool. Or find another source of the livestream from the original recording.

No, however, you might ask whoever put on the livestream if there is a recording.

You can re-record the audio and add it with a program like iMovie.