I can't access my File Manager and not able to troubleshoot WordPress

[Admin]

@SageUD

Just one more thing, I want to login to WordPress from their website as opposed to going through Softaculous > wp-admin.
Where can I get that username and password ?

From the Softaculous settings, you can find/configure the Admin Username and Admin Password.

With those credentials set, you can login directly on http://firebrixs.com/wp-admin/

As you’re using self hosted WordPress (wordpress.org), it doesn’t rely on the hosted WordPress (wordpress.com) to work, and doesn’t integrate with it unless you want it to.