You can set up single sign-on for your WordPress users to easily log in to Freshdesk using the Freshdesk plugin for WordPress.

You can use the plugin to enable your users to seamlessly and securely log in to Freshdesk. To do so, you first need to install the Freshdesk WordPress plugin. You can install the plugin from the plugins directory if your site runs on self-hosted WordPress. If you use, you need to be on the Business plan or above to install this plugin. 

Click here to read a step-by-step guide on authenticating WordPress users into your Freshdesk account in more detail.