Spinupwp is a great new way to manage WordPress sites on Digital Ocean. Fortunately or Unfortunately, they handle access to the server in a more limited version that dealing directly with Digital Ocean.
Cutting to the chase, Spinupwp will not let you access the server via ssh with the root user or with password authentication.
Once you’ve done these two steps, you’re free to ssh into your Digital Ocean server using the sudo user. It will look something like the following: