Command Line Ubuntu Expert To Fix Permission

Hello, I am looking for some immediate help. Autobids will be ignored. If you bid please be available now to help. I am looking for someone who is great at System admin, console and knows WordPress and Php. Basically, we are using Vultr and RunCloud for our server. We were getting an error that said upload directory was not writeable. I saw something that said the following to fix it: chown -R www-data:www-data /var/www/ chmod -R 766 /var/www/ The above was for a Digital Ocean server. Vultr doesn't have the same directories so I did /home/application-name, and I forgot the end "/". Now when trying to access the website we are getting a "File Not Found" error in the browser. We need the following: 1. Fix the permission issues or what is causing this so the page can load fine 2. Fix the upload directory permission so that it is able to be wrote to. 3. Help migrate this to the new domain (it is pretty much setup just need to change nameservers and some DNS). If this is not fixable, how can we get copies of the database because right now I cannot access the database via phpMyadmin because of the error and changes had been made to the site since we moved it.