If you're new to Mastodon: welcome!
Here are a couple guides I've put together:
An Increasingly Less-Brief Guide to Mastodon, which tries to explain what this place is all about: https://github.com/joyeusenoelle/GuideToMastodon/
So You're A Mastodon Moderator, which has some information on the tools at your disposal and some best practices for using them (it needs an update, but is still generally accurate): https://noelle.codes/so_youre_a_mastodon_moderator.pdf
The social network of the future: No ads, no corporate surveillance, ethical design, and decentralization! Own your data with Mastodon!