This podcast from The New York Times is an interesting discussion with the host along with David Wallace-Wells (The Uninhabitable Earth) and Genevieve Guenther (author and PhD professor at Tishman Environment and Design Center at The New School (and Director of EndClimateSilence.org)
Per the podcast, here's what you can do: Vote, join a campaign/activist group, direct action, donate money to groups like Sunrise and Fridays for Future etc., Talk about climate change especially when it's the most awkward. (do this once a week- except vote, obviously)
The Argument: Got Climate Doom? Here’s What You Can Do to Actually Make a Difference on Apple Podcasts
Good advice - I think there is an aspect of avoidance for some people when they say "what can I do?" (Not all of course.) A phrase cousin of the plaintive "What can ya do?" I've taken to telling people that a better question is "What am I going to do?" Most people know things they can do, they just need to get going and do them.