Despite having a CS degree I actually never took a web programming course as my small liberal arts college didn't have one. So, I taught myself everything I know about it using free resources off the Internet. If I did it, so can you!
Instead, I recommend Khan Academy's free courses since they are constantly having you do little challenges and projects that apply everything you've learned so far in an environment closer to a real website. The most applicable ones for making a Neocities site will be the HTML/CSS one and then the HTML/JS one, but I encourage you to take a look at the rest too. I had a lot of fun with the Advanced JS courses in games and simulations! Then once you've learned the basics, if you ever forget a piece of syntax you can look it up quickly on w3schools.
A more advanced resource would be Mozilla Developer Network, which has both very in-depth documentation for web development technologies and some pretty helpful tutorials. For responsive design and more advanced CSS stuff I like Kevin Powell's YouTube channel.