If you've accidentally deleted a website, in most cases you can get it back up and running pretty quickly.
First, create the website again using the same url on the same server.
Once provisioned, click on the websites name to open up the configuration modal and then click on the backups tab.
Select a backup from the dropdowns and click "Restore Now".
This will work in most cases. The only times this may not is if you just deleted a brand new website and chose not to back it up when you confirmed it's deletion. Or, if you manually turned backups off, and then chose not to back it up when you confirmed it's deletion.