GDPR seeks to balance the rights of the individual against the wider rights of the general public. Local Government legislation allows any member of the public to video any of your meetings and broadcast that video anywhere they choose. As public servants, we surrender our right to privacy. Members of the public attending our meetings should be made aware that they may be recorded for broadcast, in the same way that they might be when walking down any street in this country, with the proliferation of CCTV cameras, or attending any televised sporting event. We don't own our image in a public place. Even children lack any legal protection in this regard, as long as they are in a public place, not on private property.
As a Clerk, I advise people to position themselves against a plain wall when using Zoom, as it provides a much better picture. If you have adopted a documented internal procedure to delete the video and audio file after the minutes have been published, then continue to do so and don't share them. If it isn't a formal policy of the council and somebody has submitted an FOI, you should not delete them.
For the correspondence request, you could redact all personal information. You should still perform the usual tests in determining whether or not to provide the information, based on the circumstances.