Teleprompter, background blur, captions, music and export in one workflow.
The usual reason people never post a talking video is the retake loop: one stumble, start over, give up. Do not aim for a perfect take. Record the whole script once at a slightly slower teleprompter speed than feels natural, then watch it back. A calm, complete take almost always beats a perfect first ten seconds.
No. It is only on your screen while you record.
Yes. Set it before you start and adjust it during the recording.
No. The phone or laptop microphone is used, and captions carry the words for people watching without sound.