Wayne, First think is to update your Zoom version--very important since this is a new feature. Go here for PC or MAC. This would be the first thing to try since captions just came out for Zoom Pro:

https://zoom.us/download

And Chromebook, I found it here (upper right corner)
December 9, 2020 version 5.0.0 (4241.1207)
Chrome Web Store

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