The URLs of the content you publish on your site are called Permalinks. Permalinks are what people enter into their browser address bar to view a page on your website. They’re also what search engines and other websites use to link to your website.
You can change the structure of your Permalinks at any time, however doing this will change the URL of your pages. Changing your URLs can cause 404 page errors on your site if a visitor lands on a page that used to have a different URL. Because of this, we don’t recommend changing your Permalinks if you have an established website. It is best to configure your website with the recommended Permalink structure at the very beginning.
By default, the Permalink structure looks like this: http://yourwebsite.com/?p=123456. This URL is not a user-friendly link and is not SEO-optimal. Which is easier to navigate to, http://yourwebsite.com/?p=123456 or http://yourwebsite.com/about?
To change your Permalinks, go to your WordPress dashboard > Settings > Permalinks.
The two Permalink structures that are best and will benefit your site most are either Post Name or this custom structure: /%category%/%postname%/