I am by no means a webmastery expert, but given that I am a novice, I think I can help other novices in their journey, because I am right there with you, in these HTML trenches, figuring this shit out day by day. This will also serve as a credits page, where I'll link where and how I added certain things to this site.
I am going to outline how I got started on Neocities, step by step, so that you, too, can get started. This is to make a site where each page has basically the same layout, but with different content. That said, you can also have each page look different, but I didn't do that so that's not what this guide will be.
1. Make a Neocities account.
2. Visit Sadgrl online's layout builder. Use it to make a layout.
2a. You'll notice the layout has a section with HTML, and a section with CSS. Even if you're a novice, sadgrl has done us the great favor of stating "THIS IS THE CSS" in the code. The part on top is the HTML. The part on bottom is the CSS.
3. Make two files in Neocities called index.html and style.css.
This will make it so you can change the appearance of your entire site all at once, should you want to, as long as your HTML files link to your CSS stylesheet.
5. Split your new layout code in two.
5a. Put the css part in style.css, and the rest in the index.html file, between the <body></body> tags. When you make a new file in Neocities, it will come with the basic formatting needed.
5b. Your HTML file will come with a link to your stylesheet, and it will work if you titled it style.css
7. Click save on both files. Then click the red "View" button on the HTML file.
Does your site look like the preview in Sadgrl's layout builder? If so, nice job! If not, then it's gonna take some tinkering. I can't diagnose your problem from here, as I am not looking at your code. You can hit me up though. nicothepoet(at)gmail.com. That said, I am sometimes bad at responding to messages, so if you want a response sooner, I recommend joining a coding discord. Those folks are often very rad.
8. Now the fun part! Customizing.
Through some persistence and pattern recognition, you will probably start to understand what part of the code is doing what. Time to start filling in text, gathering resources (images, backgrounds, blinkies, etc.), changing colors, etc.
9. Frequently save your work and refresh your page to make sure you didn't break something.
10. When you eventually break something:
go on your website, right click the broken thing and select the "Inspect" option (I have Firefox. This might be called something else in your browser. It's the thing that opens up a panel that shows the code for the thing you clicked on.) Examine the code. See if you can figure out how you broke it. If you can't figure out how you broke it, Google the issue or ask in the aforementioned Discord.
11. Once your first page is done, copy-paste it onto a new html file and do it all over again for your second page.
Most of my webmastery journey has involved trying to do a thing, doing it bad, Googling it, trying to do it again, and maybe eventually succeeding. Thankfully, that's a process I thoroughly enjoy.
P.S. You have my permission to use any code from my website. Just please don't hotlink (try to save any images you use to your own Neocities files and link to that) and credit me.