This is what my hosting service provider (Digital Ocean) wrote back:
There has been a response to your ticket:
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Thank you for submitting a ticket with us today!
I see that you are using a normal Ubuntu image, so we wouldn't really know where your Wordpress directory is.
This would be wherever you installed Wordpress on your droplet.
You can always pull up your virtual host in /etc/apache2/sites-available/ and see where the DocumentRoot is located.
Let us know if you have any additional questions or concerns.