There is a demo in the flows library that will get you started...
https://flows.nodered.org/flow/c70d0b4c54b583cf30c7e989b74feb68
...You dont necessarily need the frontend stuff (you can remove it).
As for https/certs - search the forum (this has been covered a few times) - here is one such article
As for "credentials (username and password)" see the official documentation "securing-node-red"
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