It's easy to give some generic advice, which may or may not help. Becoming an "expert" (knowing something well, not intended to mean knowing more than the audience) can increase your confidence. The tangential aspect is dealing with "impostor syndrome", which will work against you.

For presentations, there are books and videos to learn from. But what matters is practice, which can be done in safer spaces and smaller groups.

Lastly, this sentence in Steve Jobs's commencement speech at Stanford in 2005 [1] could help:

> "Remembering that you are going to die is the best way I know to avoid the trap of thinking you have something to lose."

Realizing that everything is impermanent, and that whatever you think or others think today may not stay around in a decade or few from now, also helps. It is ok not to be good at presentations or speaking to an audience. Not everyone is cut out to be a great speaker or a good presenter. Focus on your strengths and derive satisfaction from those. Frame this or keep this around in some form: "This too shall pass".

[1]: https://www.rev.com/blog/transcripts/steve-jobs-stanford-com...