Permalinks

Hi,
Normally I would just do this by going to the Dashboard, then Settings–>Permalinks and selecting Post Name, then Update. However, that is for NEW sites. Do you have posts on this site already, or is it a new site? Be aware that if you update permalinks on a site with pre-existing posts, those URLs will change, so any links to them on other sites will no longer work.

If you find the Codex challenging, as many do, this link might also be helpful:

https://www.wpexplorer.com/change-permalinks-wordpress/

Hi Thanks! it’s an already existing site with previously posted articles. That’s why I have to chance the .htaccess I’m assuming.

OK, there’s just two pieces from that article that I want to be extra sure to draw your attention to:

Once you know which syntax you are going to use, it is time to go into the Permalinks menu of your dashboard and make the change. This will now update all of your internal URLs with the new syntax. All of the internal links should update correctly if they have been added as part of WordPress. Any manual links may need to be updated.
However, all links to your site from elsewhere will now be completely broken and all the content indexed by search engines will be incorrect.

and

In the past you would have been required to add all of these redirects manually to your .htaccess file on your web server. Thankfully, with WordPress there are plugins that can take care of all of these things for you. To easily create the redirects on your WordPress website I recommend the Simple 301 Redirects plugin.

This plugin should remove the need to manually update the .htaccess file, one of the functions of which is to redirect users.

Please back your site up, especially the database, before you proceed.