Knowing what wordpress version you are using is very imporntant . You MUST to run latest versions for security and stability of your website
The latest version of wordpress can be found here
1. Easiest Option: Log onto the admin URL .
Search for “At a Glance” and explore or Scroll down and at the extreme bottom right
2. On the main page, view page source , search for generator
3 WordPress Login Screen: Viewing Source Code and search for ver=
4. Log onto cpanel, Then domain/wp-includes/version.php