How can I make my narration + and video of myself talking it through sync with individual slides?

I'm adding on to the question I just reviewed " How can I make my narration sync with individual slides

" from 2020.

I am creating an elearning with iMovie and want to also talk it through not only with audio bug as a "talking head" with video.

So far I've got the ppt as pictures dropped in to the media and have also been able to record my voice with it. But how to also do it as video/audio?

thanks for your answers!