There are many things you can do to keep WordPress running smoothly and efficiently.
Avoid displaying a lot of posts on your homepage or blog pages. Doing so makes your site load slower, especially if your posts are image-heavy.
Also, fewer posts on your blog’s homepage can make it much easier for those reading on mobile (less scrolling).
How to change the number of posts on your blog pages
In WordPress, go to Settings –> Reading –> “Blog pages show at most ___ posts.”
I recommend keeping your post count to 4 or 5 max.
Don’t forget to save your changes!