With web development as with many other things being able to experiment increases your chance to solve a problem, like reprex for R.
Create a new distill/Hugo website and play in it. You might like this Lorem Ipsum Hugo shortcode.
Create a free wordpress.com website (with which you cannot use goodpress, though), or some other sort of throw away Wordpress instance.
For HTML+JS+CSS independently from website generation, use a code playground such as CodePen (or build your own for blog posts 😸).
For sketching layouts apart from drawing on paper 😁 there are tools like Figma (that has a free version) and Sketch (macOS only, no free version).