Welcome to the mautrix-discord docs!
Use the sidebar to find the relevant pages. Things that are the same for all bridges, like setting up the bridge, are right below the "Go-based bridges" header. Things specific to mautrix-discord are under this page.
These docs are mostly targeted towards people who are hosting the bridge themselves. If you don't want to host it yourself, you can use a public instance. When using public instances, refer to their instructions and support rooms.
If you run a public instance and wish to list it here, please make a pull request.
Matrix room: #discord:maunium.net