As we can see, you just installed the WHMCS template. That’s why you got the WHMCS homepage. Moreover, WHMCS does not support RTL, that’s why it shows like that.
Please Note: Mainly, our item is a WordPress theme and we have just provided the WHMCS template for FREE of cost to use separately with our theme by customizing the WHMCS default six template’s header, footer, and color based on our WordPress theme.
In this issue, you need to use both WordPress theme and WHMCS templates separately. WordPress theme to show/represent your products/services and WHMCS template for billing like as our theme live demo. Moreover, you need to link up all of your products/services (buy now link) to your WHMCS.