What language should I learn to create an authentication website?

The website functions by a user inputting their email address and self-generated password. I am leaning towards node.js. What language will be sufficient to create such an authentication-based website? On the front-end, my skills are HTML, CSS and JavaScript. E.g a user inputs their details, i.e email: example@gmail.com, and password: examplePassword, then they are able to access the next page if the details entered match those used to sign up. Thanks