How to turn off comments in WordPress
The default configuration of WordPress allows users to submit comments to posts on your site. If you want to turn off the comments function, you can do that very quickly and easily from the admin panel of your WordPress.
After you log in go to Settings menu>Discussion, on the page that opens unmark the checkbox for Allow people to post comments on new articles and click on the Save Changes button. This will disable the function for all new posts/articles (the ones that are made after you change the setting).
To disable comments for existing posts, in the admin panel go to the Posts menu on the left, on the page that opens mark the checkboxes for the old posts, select Edit from the Bulk Actions drop-down menu and click on the Apply button next to it. On the following page select Do not allow from the Comments drop-down menu and click on the Update button.