How to Make a Beautifual Website

Good design has the following goals:

To make the most important information the easiest to find.
To answer your questions in the order you're likely to have them.
To place more specific information exactly where you'd expect it.
To make sure you can focus on one thing at a time without being distracted by other information or content.
To use colors, fonts, and layout to help you focus (not to distract).

Therefore, good design is usually characterized by the following:

Large text, widely spaced, and condensed down to the most important information. You almost always have to click to learn more.
Lots of negative space (areas with no content) to direct your focus onto what little is there.
- Pro-tip that the "padding" property is one of the best ways to achieve this.
Clear design hierarchy (the most important info is up top, in large fonts; more specific info is in smaller fonts, and usually further down)
Consistency across similar elements.
Intentional, simplistic font choices. Even though it's tempting to use really bubbly, playful, or decorative fonts, most of the best and most beautiful websites use only two fonts: one for headers, another for body text, and the vast majority of websites use thin and block versions of sans-serif fonts.

Over the course of the 2010s, web design trends have been dominated by two major schools of thought:

Material Design: This particular guide was written by designers at Google, and was the guiding light for a lot of systems you may be used to using, though they're gradually moving away from or at least evolving this school of thought in current updates.
Flat Design: Microsoft has historically been the largest proponent of flat design (as early as the mid 2000s with many of their products), though Apple has largely shifted their design to Flat Design as well.