To access the important data of the forums, you must be active in each forum and especially in the leaks and database leaks section, send data and after sending the data and activity, data and important content will be opened and visible for you.
You will only see chat messages from people who are at or below your level.
More than 500,000 database leaks and millions of account leaks are waiting for you, so access and view with more activity.
Many important data are inactive and inaccessible for you, so open them with activity. (This will be done automatically)
WHMCS API doesn't have a function to change the language. Therefore, your best bet would be to use an action hook, and when that hook executes, you would need to change the language by directly interacting with the database. You would directly use a `mysql_query()` function, since the connection is already established by WHMCS itself.