There isn’t much to it.
Digital Ocean provides you with a Linux virtual server that is connected to the internet. It is up to you how/what that server does, you are the system administrator and will need to setup everything to suit your requirements (beyond the initial distribution and ssh connectivity).
There are plenty of guides that can help you to do this, although you will need to understand how Linux works, and some general conventions, otherwise it may be a steep learning curve.
Head over to the tutorials section and start researching what environment you will need.
Tutorials | DigitalOcean