Learn X in Y Minutes[1]. Shows you all of the things you need to know in a programming language in code, with fully commented examples. I use it mostly as a reference, but I used it to learn some languages, such as C++, Rust, and Vala. When I was young, I was given a "Get Coding!"[2] book (the first one), which covers the basics of web development, HTML, CSS, and JavaScript, which really jumpstarted my programming career.

[1]: https://learnxinyminutes.com/

[2]: https://getcodingkids.com/