How do I configure my linode to send emails

Look at the first FAQ item above.

— sw

OK thanks, and where is the guide to set it up?

Here are the guides for Linode that can give you a variety of documentation on many different things. And, more specifically, a guide to setup Postfix on Ubuntu 22.04. A google search helped me find the second easily, though sadly, it wasn't available on Linode's documentation, that I could find.

I hope this was helpful for you. Good luck.

Blake