[Wex19] Unit 2, Lesson 8.

The https://nodejs.org/en/ website.

The https://expressjs.com/ website.

And a couple of tutorials:

The https://developer.mozilla.org/en-US/docs/Learn/Server-side/Express_Nodejs website. An Express tutorial with a MongoDB database. Read it, then start with the first step in the Guides section.

An Express tutorial without a database https://shapeshed.com/creating-a-basic-site-with-node-and-express/