I understand, I also do webinar composing and I will say for sure that it is not an easy task. But here you should take a look and get acquainted with different recommendations that can help with this https://www.movavi.com/support/how-to/how-to-record-zoom-meeting.html . With their help, I now manage to regularly make a recording of conferences via Zoom and post it on the website. It's quite convenient, and also the quality of both video and sound is good, without unnecessary noise. Therefore, it is worthwhile to read about it and proceed step by step exactly as described in the article.