Installing WHMCS in WordPress is a fairly simple process. First, you will need to create a WHMCS account. After you have an account, you will need to login and navigate to the WHMCS Dashboard. From here, you will need to select the WordPress installation that you would like to manage.
Once you have selected the WordPress installation, you will need to click on the Install button. After you have clicked on the Install button, WHMCS will begin to install the necessary modules. Once the installation process has been completed, you will need to click on the Activate button to activate the WHMCS installation. Finally, you will need to navigate to the WHMCS WordPress Administration Panel and set up your WHMCS account.