If you're interested in learning vanilla JavaScript through an online course, you might like to try Execute Program: https://www.executeprogram.com/

I found it more thorough and challenging than others I've tried, but it doesn't assume any knowledge of JavaScript.

I have a question about an embarrassingly simple problem: "Element Access". Is there a way I could contact you about it?

If by “Element Access” you mean getting pointers to DOM elements, try querySelector [1] or querySelectorAll [2]:

  var element = document.querySelector(...)

  var elements = document.querySelectorAll(...)

[1]: https://devdocs.io/dom/document/queryselector

[2]: https://devdocs.io/dom/document/queryselectorall

Feel free to email me. My Gmail address is "parodieslost". Although I'm not affiliated with Execute Program, I have done the JavaScript Arrays course (including Element Access), and I'd be interested in your problem.