Once you register an account, Discourse guides you with the first steps.
You’ll recognise the notifications and find out about discobot, a gentle bot which helps you learning to use this platform
I won’t spoil you with the details, only one thing - you can earn a badge for completing the tutorial with discobot.
If you cannot find the private message, just send a new one to @discobot and include the following text:
start new user
In case you have further questions, please create a new topic in the Site Feedback category.
Once you’ve completed the basic tutorial, start the advanced tutorial with
@discobot start advanced user. This grants you a second badge