One thing i regularly look up is how to create a new Postgres User & DB. So here are the two ways to create a User and Database.

The CLI Way

Postgres has many helpful Utilities for some common operations.

Like for creating a User (the -P will Prompt for a Password):

1sudo -u postgres createuser -P gitea

And creating a Database with assigned permissions:

1sudo -u postgres createdb --owner gitea gitea_db

You can add --echo to those commands to see the actual SQL that is send to the Database.