As of December 2019, PHP 5.6, 7.0, and 7.1 have been removed from the DreamHost panel. Any sites on a Shared server running PHP 5.6 or 7.0 are in the process of being upgraded to PHP 7.2. Websites on VPS and Dedicated servers will continue to run older versions of PHP for the time being.
If you would like to manually change the PHP version of your site, the current options are 7.2, 7.3, or 7.4. For more information, see the following article:
What if my site was previously using PHP 5.6, 7.0, or 7.1?
Any sites on a Shared server previously running PHP 5.6, 7.0, or 7.1 are in the process of being automatically upgraded to PHP 7.2.
It's highly recommended that you upgrade your sites to PHP 7.2, 7.3, or 7.4 as older versions will soon be removed completely from all DreamHost servers.
For more information on updating your site's PHP version, view the following article: